lsat 12-7,lsat 14-4

lll123

lsat 12-7
Every adult male woolly monkey is larger than even the largest female woolly monkey. In colonies of woolly monkeys, any adult male will dominate any female.
If the statements above are true, which one of the following must on the basis of them be true of woolly monkeys in colonies?
(A) Size is the primary determinant of relations of dominance among woolly monkeys.
(B) Some large adolescent male woolly monkeys dominate some smaller females of the species.
(C) If a male woolly monkey is larger than a female of the species, that male will dominate that female.
(D) If a female woolly monkey dominates a male of the species. the dominated male monkey is not an adult.
(E) An adult male woolly monkey can dominate a female of the species only if that female is also an adult.
答案是：D，为什么不是A?

LSAT14-4
Conservationists have established land reserves to preserve the last remaining habitat for certain species whose survival depends on the existence of such habitat. A grove of trees in Mexico that provide habitat for North American monarch butterflies in winter is a typical example of such a land reserve. If global warming occurs as predicted, however, the temperature bands within which various types of vegetation can grow will shift into regions that are currently cooler.
If the statements above are true, they provide the most support for which one of the following?
(A) If global warming occurs as predicted, the conservation land reserves will cease to serve their purpose
(B) Monarch butterflies will succeed in adapting to climatic change by shortening their migration
(C) If global warming occurs, it will melt polar ice and so will cause the sea level to rise so high that many coastal plants and animals will become extinct
(D) The natural world has adapted many times in the past to drastic global warming and cooling
(E) If global warming occurs rapidly, species of plants and animals now protected in conservation land reserves will move to inhabit areas that are currently used for agriculture
为什么选A？最后一句话什么意思？（If global warming occurs as predicted, however, the temperature bands within which various types of vegetation can grow will shift into regions that are currently cooler.）

mindfree

1. It just cannot be A. Typically A is what you conclude based on your assumption and D is absolutely correct. Remember, CR is to test your logic reasoning, not how you can rely on the evidence and your own assumption to reach a conclusion.

In this one, it is like saying: X, Y happens at the same time. Your conclusion (A) is: X causes B. The conclusion is unwarranted. Something else can cause Y, or as a matter of fact Y causes X. You never know for sure.

What is definite is that if A --> B, then not B --> not A. Basic logic reasoning tested in GMAT.