【每日逻辑练习第二季】【2-17】

xiongyz

1.    41s
P: In humans, ingested protein is broken down into amino acids, all of which must compete to enter the brain. Subsequent ingestion of sugars leads to the production of insulin, a hormone that breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan. Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain’s serotonin level.
C: Thus, sugars can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.
Assumption: insulin和Tryptophan 能让人relax和anxiety-free
(A) Elevation of mood and freedom from anxiety require increasing the level of serotonin in the brain. ---reverse answer, relax? serotonin level升
(B) Failure to consume foods rich in sugars results in anxiety and a lowering of mood. ---否命题成立，原命题不一定成立
(C) Serotonin can be produced naturally only if tryptophan is present in the bloodstream. ---无关
(D) Increasing the level of serotonin in the brain promotes relaxation and freedom from anxiety. ---correct, 结论为sugar?relax, 前提是sugar? serotonin level升，所以p: serotonin level升?relax
(E) The consumption of protein-rich foods results in anxiety and a lowering of mood. ---无关

2.    50s
Twenty percent of the stores in Morganville's downtown shopping district will fail within five years because they will be competing directly with the SaveMart discount department store newly opened in East Morganville.  The downtown shopping district has lost business at this rate before and has always completely rebounded.  however, because __________.
C: Confidence that it will rebound again from the losses it is now about to suffer is ill founded
Complete: 过去能rebound不代表现在能rebound, 或者有恶化不能恢复的原因
A. the stores likely to be put out of business by direct competition from SaveMart are the downtown shopping district's anchor stores, on whose ability to draw shoppers many of the other downtown stores depend ---没怎么看懂 吸引顾客的能力取决于与之竞争的anchor stores？
B. the bus line that has long connected the downtown area of Morganville with East Morganville has a tradition of carrying shoppers who reside in East Morganville into downtown Morganville to shop ---weaken…
C. when the downtown shopping district has rebounded before, the business premises of a failed business were typically taken over by a business of the same kind as had been there before ---irrelevant, 提出以前rebound的原因, 没说现在
D. SaveMart's business plan for the East Morganville store is based on earning low profits, if any, during the first five years of the store's existence ---irrelevant
E. it is conceivable that the downtown shoping district could shrink substantially without collapsing altogether ---correct maybe
这题做得我有点蒙。。。
正确答案：A   求解释。。。

3.    43s
P: the country's legislature decided to implement a plan that allows investors to save up to $1,000 per year in special accounts without paying taxes on the interest earned unless withdrawals are made before the investor reaches age sixty-five. Withdrawals from these accounts prior to age sixty-five would result in the investor's having to pay taxes on all the accumulated interest at the time of withdrawal.
C: To improve the long-term savings rate of the citizens of Levaska,
Support: 银行有支付增加的interest的能力；通货膨胀不会高于增加的rate，人们会invest…
A. The money saved in the tax-free savings accounts will be deposited primarily in those banks and financial institutions that supported the legislation instituting the plan. ---无关
B. The majority of people choosing to take advantage of the tax-free savings accounts will withdraw their money prior to age sixty-five. ---weaken
C. A significant number of the citizens of Levaska will invest in the tax-free savings accounts well before they reach the age of sixty-five. ---correct
D. During the ten years prior to implementation of the plan, Levaskans deposited an increasingly smaller percentage of their annual income in long-term savings accounts. ---无关
E. People who are not citizens of Levaska are not eligible to invest in the tax-free savings accounts, even if their income is taxable in Levaska. ---无关

4.    34s
B: In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation.  
P: The spread of such extinctions closely followed the pattern of human migration.  However, since humans tended to migrate to areas as the climate in those areas began to warm
C: the extinctions might have been precipitated by the climatic warming rather than by human migration.
Weaken: human刚迁徙进的地方不warm，但是动物还是extinct了
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there. ---另一个与文中类似的fact, 不能说明
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct. ---说明是climatic warming, opposite answer
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming. ---correct, 天气热但是没有人，动物survive, 说明是人的活动造成的灭绝
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals. ---无关，未提到天气
E. Some large animals had become extinct in Europe even before humans migrated there. ---无关

5.    42s
P: In many scientific disciplines, scientists generally do not do highly creative work beyond the age of forty, a tendency that has normally been taken to show that aging carries with it a loss of creative capacity.  However, by the age of forty most scientists have been working in their chosen field for at least fifteen years,
C: so an alternative explanation is that spending too long in a single field reduces the opportunity for creative thought.
Evaluate: 没有长时间在一个领域工作的是否保持了创造性的思维
A. Whether among those scientists who do highly creative work beyond age forty a large proportion entered their field at a considerably later age than is common ---correct, yes则结论错，no则结论对…
B. Whether scientists' choice of research projects tends to be influenced by their own belief that their most creative work will be done relatively early in their career ---无关
C. Whether scientists who are older than forty tend to find more satisfaction in other activities, such as teaching and mentoring, than they do in pursuing their own research ---无关
D. Whether funding agencies are more inclined to award research grants to scientists who are veterans in their field than to scientists who are relative newcomers ---无关
E. Whether there is significant variation among scientific fields in the average age at which scientists working in those fields are at their most productive ---无关

penguinsdz

11.08+【2-17】

1. In humans, ingested protein is broken down into amino acids, all of which must compete to enter the brain. Subsequent ingestion of sugars leads to the production of insulin, a hormone that breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan. Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain’s serotonin level. Thus, sugars can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.
Which one of the following is an assumption on which the argument depends?
(A) Elevation of mood and freedom from anxiety require increasing the level of serotonin in the brain.
(B) Failure to consume foods rich in sugars results in anxiety and a lowering of mood.
(C) Serotonin can be produced naturally only if tryptophan is present in the bloodstream.
(D) Increasing the level of serotonin in the brain promotes relaxation and freedom from anxiety.
(E) The consumption of protein-rich foods results in anxiety and a lowering of mood.

Premise:
ingested protein is broken down into amino acids
Premise:
Subsequent ingestion of sugars leads to the production of insulin;

Insulin breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan; Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain’s serotonin level.

Conclusion:
Thus, sugars can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.

选项分析：选D



2. Which of the following most logically completes the argument below?
Twenty percent of the stores in Morganville's downtown shopping district will fail within five years because they will be competing directly with the SaveMart discount department store newly opened in East Morganville. The downtown shopping district has lost business at this rate before and has always completely rebounded. Confidence that it will rebound again from the losses it is now about to suffer is ill founded, however, because __________.
A. the stores likely to be put out of business by direct competition from SaveMart are the downtown shopping district's anchor stores, on whose ability to draw shoppers many of the other downtown stores depend
B. the bus line that has long connected the downtown area of Morganville with East Morganville has a tradition of carrying shoppers who reside in East Morganville into downtown Morganville to shop
C. when the downtown shopping district has rebounded before, the business premises of a failed business were typically taken over by a business of the same kind as had been there before
D. SaveMart's business plan for the East Morganville store is based on earning low profits, if any, during the first five years of the store's existence
E. it is conceivable that the downtown shopping district could shrink substantially without collapsing altogether

Background Information:
Twenty percent of the stores in Morganville's downtown shopping district will fail within five years because they will be competing directly with the SaveMart discount department store newly opened in East Morganville.

Conclusion:
Confidence that it will rebound again from the losses it is now about to suffer is ill founded.

选项分析：选A??



3. To improve the long-term savings rate of the citizens of Levaska, the country's legislature decided to implement a plan that allows investors to save up to $1,000 per year in special accounts without paying taxes on the interest earned unless withdrawals are made before the investor reaches age sixty-five. Withdrawals from these accounts prior to age sixty-five would result in the investor's having to pay taxes on all the accumulated interest at the time of withdrawal.
Which of the following, if true, most strongly supports the prediction that the legislature's plan will have its intended effect?
A. The money saved in the tax-free savings accounts will be deposited primarily in those banks and financial institutions that supported the legislation instituting the plan.
B. The majority of people choosing to take advantage of the tax-free savings accounts will withdraw their money prior to age sixty-five.
C. A significant number of the citizens of Levaska will invest in the tax-free savings accounts well before they reach the age of sixty-five.
D. During the ten years prior to implementation of the plan, Levaskans deposited an increasingly smaller percentage of their annual income in long-term savings accounts.
E. People who are not citizens of Levaska are not eligible to invest in the tax-free savings accounts, even if their income is taxable in Levaska.

Background Information:
The country's legislature decided to implement a plan that allows investors to save up to $1,000 per year in special accounts without paying taxes on the interest earned unless withdrawals are made before the investor reaches age sixty-five.

Premise:

Withdrawals from these accounts prior to age sixty-five would result in the investor's having to pay taxes on all the accumulated interest at the time of withdrawal.
Conclusion:
improve the long-term savings rate of the citizens of Levaska
选项分析：选C



4. In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation. The spread of such extinctions closely followed the pattern of human migration. However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
Which of the following, if true, provides the best evidence that it was human migration and not climatic change that precipitated the extinctions?
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.
E. Some large animals had become extinct in Europe even before humans migrated there.

Background Information:
In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation.
Premise:
The spread of such extinctions closely followed the pattern of human migration.
Conclusion:

However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
推测(Prephrase: mentally formulate your answer to the question stem)：
Many animal species survived longer in areas that experienced intense climatic warming.

选项分析：选C



5. In many scientific disciplines, scientists generally do not do highly creative work beyond the age of forty, a tendency that has normally been taken to show that aging carries with it a loss of creative capacity. However, by the age of forty most scientists have been working in their chosen field for at least fifteen years, so an alternative explanation is that spending too long in a single field reduces the opportunity for creative thought.
Investigating which of the following would be most useful in choosing between the competing explanations described above?
A. Whether among those scientists who do highly creative work beyond age forty a large proportion entered their field at a considerably later age than is common
B. Whether scientists' choice of research projects tends to be influenced by their own belief that their most creative work will be done relatively early in their career
C. Whether scientists who are older than forty tend to find more satisfaction in other activities, such as teaching and mentoring, than they do in pursuing their own research
D. Whether funding agencies are more inclined to award research grants to scientists who are veterans in their field than to scientists who are relative newcomers
E. Whether there is significant variation among scientific fields in the average age at which scientists working in those fields are at their most productive

Background Information:
In many scientific disciplines, scientists generally do not do highly creative work beyond the age of forty

explanation 1:

a tendency that has normally been taken to show that aging carries with it a loss of creative capacity

explanation 2:
so an alternative explanation is that spending too long in a single field reduces the opportunity for creative thought.

Evaluation:

选项分析：选A

zxppx

4.

In humans, ingested protein is broken down into
amino acids, all of which must compete to enter the
brain. Subsequent ingestion of sugars leads to the
production of insulin, a hormone that breaks down
the sugars and also rids the bloodstream of residual
amino acids, except for tryptophan. Tryptophan then
slips into the brain uncontested and is transformed
into the chemical serotonin, increasing the brain’s
serotonin level. Thus, sugars can play a major role in
mood elevation, helping one to feel relaxed and
anxiety-free.
Which one of the following is an assumption on
which the argument depends?
(A) Elevation of mood and freedom from anxiety
require increasing the level of serotonin in
the brain.

From the conclusion, we can know that the function of sugars is a sufficient condition to mood elevation, while this answer choice regards it as a necessary condition.
(B) Failure to consume foods rich in sugars results
in anxiety and a lowering of mood.

“Failure to consume foods rich in sugars” is outside the scope of the argument.
(C) Serotonin can be produced naturally only if
tryptophan is present in the bloodstream.

The unique condition to produce serotonin is irrelevant, since the argument reveals that the sugars can help produce serotonin.
(D) Increasing the level of serotonin in the brain
promotes relaxation and freedom from
anxiety.

Yes, this answer choice strengthens the argument by showing that the increase in the level of serotonin in the brain, a function of ingestion of sugars, is a sufficient to promote relaxation and freedom from anxiety. BA
(E) The consumption of protein-rich foods results
in anxiety and a lowering of mood.

The consumption of protein-rich foods has no effect on the argument.



77. (30754-!-item-!-188;#058&005525)
Which of the following most logically completes the argument below?
Twenty percent of the stores in Morganville's downtown shopping district will fail within five years because they will be competing directly with the SaveMart discount department store newly opened in East Morganville. The downtown shopping district has lost business at this rate这是重点，我在第一次读的时候没注意 before and has always completely rebounded. Confidence that it will rebound again from the losses it is now about to suffer is ill founded, however, because __________.

遇到不懂的单词或者比较难的语法的时候，一定要静下心来仔细思考，不要轻易放弃
A. the stores likely to be put out of business by direct competition from SaveMart are the downtown shopping district's anchor stores, on whose ability to draw shoppers many of the other downtown stores depend

我不知道anchor stores什么意思，后面的定语从句也没看懂！

Many of the other downtown stores depend on anchor stores’ ability to draw shoppers. 意思是说在这个商圈里的其他店铺主要依靠这些“靠山”来吸引顾客。

Anchor stores是“靠山店”，会影响其他许多的店，所以实际上倒闭的店会超过20%，那么文中说的“at this rate”那句话就无效了，所以这是正确答案！
B. the bus line that has long connected the downtown area of Morganville with East Morganville has a tradition of carrying shoppers who reside in East Morganville into downtown Morganville to shop

This answer choice strengthens the argument by showing that more shoppers will come here.
C. when the downtown shopping district has rebounded before, the business premises of a failed business were typically taken over by a business of the same kind as had been there before

我就是选择的C，但是有问题！因为没有倒闭的店,很可能仍然从事相同的商业活动，那么他们还是能够帮助“复苏”的
D. SaveMart's business plan for the East Morganville store is based on earning low profits, if any, during the first five years of the store's existence

文中讨论的就是未来五年内的情况，所以该答案不会起作用
E. it is conceivable that the downtown shopping district could shrink substantially without collapsing altogether

So it can still revive.



78. (24029-!-item-!-188;#058&000661)
To improve the long-term savings rate of the citizens of Levaska, the country's legislature decided to implement a plan that allows investors to save up to $1,000 per year in special accounts without paying taxes on the interest earned unless withdrawals are made before the investor reaches age sixty-five. Withdrawals from these accounts prior to age sixty-five would result in the investor's having to pay taxes on all the accumulated interest at the time of withdrawal.
Which of the following, if true, most strongly supports the prediction that the legislature's plan will have its intended effect?
A. The money saved in the tax-free savings accounts will be deposited primarily in those banks and financial institutions that supported the legislation instituting the plan.

Where the money is deposited is irrelevant.
B. The majority of people choosing to take advantage of the tax-free savings accounts will withdraw their money prior to age sixty-five.

This answer choice weakens the argument by showing that people will withdraw their money before age sixty-five.
C. A significant number of the citizens of Levaska will invest in the tax-free savings accounts well before they reach the age of sixty-five.

In this case, it points out the availability of the plan. BA
D. During the ten years prior to implementation of the plan, Levaskans deposited an increasingly smaller percentage of their annual income in long-term savings accounts.

Ten years prior to implementation of the plan is outside the scope of the argument.
E. People who are not citizens of Levaska are not eligible to invest in the tax-free savings accounts, even if their income is taxable in Levaska.

People who are not citizens of Levaska are irrelevant.



79. (30610-!-item-!-188;#058&005469)
In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation. The spread of such extinctions closely followed the pattern of human migration. However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
Which of the following, if true, provides the best evidence that it was human migration and not climatic change that precipitated the extinctions?
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.

This answer choice demonstrates that human migration is not the main reason of extinctions.
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.

This answer choice attributes extinction to the climatic warming.
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.

The sentence seems hard to understand. But it does point out that it was human migration and not climatic change that precipitated the extinctions. BA
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.

This still does not reveal that human migration is the main reason that precipitates the extinctions.
E. Some large animals had become extinct in Europe even before humans migrated there.

The same to D.



80. (24979-!-item-!-188;#058&001383)
In many scientific disciplines, scientists generally do not do highly creative work beyond the age of forty, a tendency that has normally been taken to show that aging carries with it a loss of creative capacity. However, by the age of forty most scientists have been working in their chosen field for at least fifteen years, so an alternative explanation is that spending too long in a single field reduces the opportunity for creative thought.
Investigating which of the following would be most useful in choosing between the competing explanations described above?
A. Whether among those scientists who do highly creative work beyond age forty a large proportion entered their field at a considerably later age than is common

In this case, it points out the age of forty is the pivot to weigh the two explanations. If the answer is yes, then the real reason is the second; otherwise, the reason is the first. BA
B. Whether scientists' choice of research projects tends to be influenced by their own belief that their most creative work will be done relatively early in their career

Actually, the two reasons can stand.
C. Whether scientists who are older than forty tend to find more satisfaction in other activities, such as teaching and mentoring, than they do in pursuing their own research

Other activities are outside the scope of the argument.
D. Whether funding agencies are more inclined to award research grants to scientists who are veterans in their field than to scientists who are relative newcomers

Awarding research grants is irrelevant to creative work.
E. Whether there is significant variation among scientific fields in the average age at which scientists working in those fields are at their most productive

The variation is very perhaps to show that after the age of forty, the production of creative work declines, still having no effect on the real reason. What’s more, we do not the variation.

angelann728

精炼 40’
逻辑链：
Premise:
(1)        蛋白质分解成氨基酸，氨基酸竞争进入大脑的机会
(2)        服用糖促进释放胰岛素 胰岛素分解糖 并且阻止氨基酸在血管中的流动 除了T的流动
(3)        T形成S S在大脑中积累
Conclusion: 糖可以影响情绪
问Assumption: D
A 削弱
B 削弱
C 重写前提
E 削弱

Prep 2:19
逻辑链
(1)        20% stores will close because of competition with S.
(2)        在之前，以这种倒闭比例，是可以completely rebounded.
(3)        However, confidence is ill founded this time.
Explain the reason: 选一个跟之前情况不一样的选项：A
B 跟之前一样 就应当说明能恢复
C跟之前一样
D 还是一样
E 还是没指出跟之前有什么差别

54’
(1)        政府为了improve saving rate 提出一个立法，立法说：65岁之前每年存1000$到一个特殊帐户不取出来就可以无税获利。
(2)        background: 65岁之前存款收获利息需要付税
问加强 选：C
A 不算很有效的支持该法案
B 算侧面加强吧 但侧重很怪
D 无关
E 削弱

39’
逻辑链：
(1)        种族灭亡是人占领居住地造成的。
(2)        however, 也可能是温度升高造成的。
问哪条可以证明是人造成的：C
ABDE全是削弱

做太多遍了A

Elisha728

8'14'
DCCCA

w.melhere

1. 1'22
2. 2'20
3. 2'30 这个错了，我把the long-term savings rate 理解为利率了，但实际应该是长期存款人所占的比例。这样就可以理解B中所说，65岁前很多人都存款，实现了long term saving。
4. 1'29
5. 1'44

苏错

12.7

【精练】

Ingested protein –amino acids

Ingestion of sugarsàproduction of insulin,but cannot break down tryptophan àT is transformedinto the chemical serotonin

Conclusion: sugars play a role in mood elevation

Assumption: Serotonin=mood elevation?

A

【逻辑链】

1.    compete with SMà20% stores willfail

beforelost business and rebounded.

Complete—A

2.    planà improve savingrate

have topay taxes on all the accumulated interest

support—C

3.    after migrationà species become extinct  follow pattern

evidence—A(C A 未提及climatic warming)

4.    tendency However alternative explanation

evaluate-- A

cyndichiang

精炼： 1‘45’‘
premise：sugars --->S ↑
conclusion：sugar can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.
Q：Assumption
prephrase:有gap，S↑--->mood elevation
(A) Elevation of mood and freedom from anxiety
require increasing the level of serotonin in
the brain.-----说了双方，留着
(B) Failure to consume foods rich in sugars results
in anxiety and a lowering of mood.----只说了mood
(C) Serotonin can be produced naturally only if
tryptophan is present in the bloodstream.----没说mood
(D) Increasing the level of serotonin in the brain
promotes relaxation and freedom from
anxiety.----说了双方，留着
(E) The consumption of protein-rich foods results
in anxiety and a lowering of mood.----protein无关
(A)实际上说反了，其实是两天逻辑链sugar-->S↑和mood--->S↑没说mood和S 的关系，D is correct。

逻辑链
1. 43’‘
premise：20% stores in downtown district will fail within 5 years
premise: 这些下降在过去也发生过并且都重新恢复了
conclusion: 但是这次的下降不会恢复
Q：support
prephrase:

2. 32’‘
premise：saveing  in special accounts without paying taxes on the interest earned
premise: withdrawals made before the investor reaches age sixty-five will pay for all the accumulated interests
conclusion: this plan can improve the long-term savings rate
Q:support
prephrase: people before 65 will invest this special accounts and no other interests-tax free accounts are availble

3. 23''
premise:humans tended to migrate to areas as the climate in those areas began to warm
conclusion:extinctions were caused by the climatic warming rather than by human migration.
Q:weaken
prehrase: when climate was warm, no extinction happened

4. 32'' 这题我见过有好多变体，当时一直做得迷迷糊糊的的，这次把它的意思自己尝试弄懂，不知道对不对
premise: 1.科学家在40岁很难有创造性的研究 ----->可能因为超过40岁就很难有创造性能力了
             2.科学家在40岁的时候已经在某领域研究很久了
conclusion: 是因为在某领域很久而导致的很难有创造性研究
Q：support
prephrase: 要证明： 40碎很难创造性成果（结果）------>因为在某一领域研究很久了（原因）
果推因：有因有果，无因无果，否定它因，因果不颠倒
因为要论证的是有因有果的例子，那么如果是有因有果就是restate结论了
那么刚进入某一新领域的上了40岁的科学家能够有创造性成果（无因无果）
因为文章要证明的就是解释结论的another explanation就是这个结论，所以在出现一个它因的可能性不大
whether scientists who study over 15 years about a subject are likely to fail in creative work?

JessieChenGMAT

myancamel 发表于 2012-1-15 00:27
premise:protein->amino acidssugars->insulin->rid the residual amino acids->except T->T increase brai ...

同意！               

May97

T: 39s
P: ingested protein is broken down into amino acids, all of which must compete to enter the brain.
P: Subsequent ingestion of sugars leads to the production of insulin, a hormone that breaks down the sugars and also rids the bloodstream of residual amino acids, except for tryptophan.
P: Tryptophan then slips into the brain uncontested and is transformed into the chemical serotonin, increasing the brain’s serotonin level.
C: Thus, sugars can play a major role in mood elevation, helping one to feel relaxed and anxiety-free.
FA: Sugar--->insulin--->tryptophan--->serotonin level--->?feel relaxed and anxiety-free
(A) Elevation of mood and freedom from anxiety require increasing the level of serotonin in the brain.--->这个选项很有意思啊。。。this answer claims that it is necessary.
(B) Failure to consume foods rich in sugars results in anxiety and a lowering of mood.--->irreverent
(C) Serotonin can be produced naturally only if tryptophan is present in the bloodstream.--->irreverent
(D) Increasing the level of serotonin in the brain promotes relaxation and freedom from anxiety.--->correct
(E) The consumption of protein-rich foods results in anxiety and a lowering of mood.--->irreverent

T: 41s
BG: Twenty percent of the stores in Morganville's downtown shopping district will fail within five years because they will be competing directly with the SaveMart discount department store newly opened in East Morganville.  
p: The downtown shopping district has lost business at this rate before and has always completely rebounded.  
C: Confidence that it will rebound again from the losses it is now about to suffer is ill founded
Support:
A. the stores likely to be put out of business by direct competition from SaveMart are the downtown shopping district's anchor stores, on whose ability to draw shoppers many of the other downtown stores depend--->correct
B. the bus line that has long connected the downtown area of Morganville with East Morganville has a tradition of carrying shoppers who reside in East Morganville into downtown Morganville to shop--->Weaken
C. when the downtown shopping district has rebounded before, the business premises of a failed business were typically taken over by a business of the same kind as had been there before--->irreverent
D. SaveMart's business plan for the East Morganville store is based on earning low profits, if any, during the first five years of the store's existence--->irreverent
E. it is conceivable that the downtown shopping district could shrink substantially without collapsing altogether--->irreverent

T: 36s
C: To improve the long-term savings rate of the citizens of Levaska,
P: investors to save up to $1,000 per year in special accounts without paying taxes on the interest earned
P: Withdrawals from these accounts prior to age sixty-five would result in the investor's having to pay taxes on all the accumulated interest at the time of withdrawal.
Support:
A. The money saved in the tax-free savings accounts will be deposited primarily in those banks and financial institutions that supported the legislation instituting the plan.--->irreverent
B. The majority of people choosing to take advantage of the tax-free savings accounts will withdraw their money prior to age sixty-five.--->weaken
C. A significant number of the citizens of Levaska will invest in the tax-free savings accounts well before they reach the age of sixty-five.--->correct
D. During the ten years prior to implementation of the plan, Levaskans deposited an increasingly smaller percentage of their annual income in long-term savings accounts.--->irreverent
E. People who are not citizens of Levaska are not eligible to invest in the tax-free savings accounts, even if their income is taxable in Levaska.--->irreverent

T: 36s
P: many large animal species became extinct soon after humans first migrated to the animals' areas of habitation.  P: The spread of such extinctions closely followed the pattern of human migration.  
-: However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
C: it was human migration and not climatic change that precipitated the extinctions?
Support: Climatic warming is also related to human migration
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.--->weaken
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.--->weaken
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.--->correct
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.--->weaken
E. Some large animals had become extinct in Europe even before humans migrated there.--->weaken

T: 46s
P: aging carries with it a loss of creative capacity.  
P: spending too long in a single field reduces the opportunity for creative thought.
EP: people who age differently but spend the same time in s field or who age the same but spend different time in a field
A. Whether among those scientists who do highly creative work beyond age forty a large proportion entered their field at a considerably later age than is common--->correct
B. Whether scientists' choice of research projects tends to be influenced by their own belief that their most creative work will be done relatively early in their career--->irreverent
C. Whether scientists who are older than forty tend to find more satisfaction in other activities, such as teaching and mentoring, than they do in pursuing their own research--->irreverent
D. Whether funding agencies are more inclined to award research grants to scientists who are veterans in their field than to scientists who are relative newcomers--->无法选择
E. Whether there is significant variation among scientific fields in the average age at which scientists working in those fields are at their most productive--->irreverent