请教一题

 In the 1960’s long-term studies of primate behavior often used as subjects tamaris, small monkeys that were thought ideal because they require only small cages, breed frequently, and grow quickly. Field studies were not used because they were costly and difficult. Tamarinds were kept caged in male-female pairs, because otherwise, serious fights erupted between unrelated females. On the basis of the fact that breeding occurred, tamarinds were viewed as monogamous.

  The view taken by the researchers concerning the monogamy of tamarinds deepened on a uestionable assumption. Which of the following could have served as that assumption?

(A) The suppression of fighting between related females serves to protect their common genetic inheritance.

(B) Adult male tamarinds contribute to the care of tamarind infants.

(C) The social system of tamarinds requires monogamous pairing.

(D) Male tamarind monkeys do not display aggressive behavior in the wild.

(E) The way the tamarinds were kept in cages did not affect their mating behavior.

建议你发帖的时候把题号也贴出来。另外你可以自己先根据题号搜索一下。似乎这题是GWD的，应该都有讨论过的。

答案是E吧。

问assumption。题目说因为这个猴子是单配偶制，所以他们在交配期打架，所以将他们成对的放在一个笼子里。

E取反，就是说是其实是因为成对地关在笼子里导致了他们的交配行为发生变化，(成了单配偶制）。因果关系搞反了。原推理就不成立了。