求助，一道prep07 CR

xn8510

Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

Which of the following, if true, most seriously undermines the argument?

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

正确答案是D。
我知道为什么ABCE不对，但是却不明白为什么D是正确的。望各路牛人解答~~~万分感谢~~~~

reebe

Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

Which of the following, if true, most seriously undermines the argument?

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

正确答案是D。
我知道为什么ABCE不对，但是却不明白为什么D是正确的。望各路牛人解答~~~万分感谢~~~~

-- by 会员 xn8510 (2012/3/23 12:05:04)

这道题的意思是：这项发现提供F自然形成时地壳的状态（措施）→实验室在相应的温度和压力下合成F（目的）。削弱这个命题就是此项措施行不通。
D选项说自然形成的F的晶体结构根本就不知道，那么也就无法根据这个来推知F自然形成时的地壳状态，措施根本就不成立。削弱了该命题。

xn8510

Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

Which of the following, if true, most seriously undermines the argument?

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

正确答案是D。
我知道为什么ABCE不对，但是却不明白为什么D是正确的。望各路牛人解答~~~万分感谢~~~~

-- by 会员 xn8510 (2012/3/23 12:05:04)

这道题的意思是：这项发现提供F自然形成时地壳的状态（措施）→实验室在相应的温度和压力下合成F（目的）。削弱这个命题就是此项措施行不通。
D选项说自然形成的F的晶体结构根本就不知道，那么也就无法根据这个来推知F自然形成时的地壳状态，措施根本就不成立。削弱了该命题。

-- by 会员 reebe (2012/3/23 18:35:04)

明白了！多谢啦~~~

bobdog159

这道题 楼主应该注重文章开头的一个词 spherical molecule。 D选项是说 自然条件下的 分子结构不清楚，所以不是球形的。 文章中说了，实验室里创造出来的分子结构是球形的。

由于分子结构不一样，无法得出产生的条件相似，或者有关联

xn8510

这道题 楼主应该注重文章开头的一个词 spherical molecule。 D选项是说 自然条件下的 分子结构不清楚，所以不是球形的。 文章中说了，实验室里创造出来的分子结构是球形的。

由于分子结构不一样，无法得出产生的条件相似，或者有关联

-- by 会员 bobdog159 (2012/3/24 17:39:49)

嗯，有道理啊~~谢谢啦~~~

ychen34

谢谢啦 终于懂了

DeliciaAn

今天这道题目错了，谢谢上面的各位的解答