In 1963, a young macaque monkey was observed venturing into a hot spring to retrieve food which had fallen in. Soon, ...

Ravi on November 11, 2020

@liwenong28, let's look. This is a strengthen with a necessary premise question, so we can negate the answer choices to see which one is correct. The correct answer choice, when negated, will wreck the argument. D's negation says, "The social behaviors of macaques are not completely independent of their genetic heritage." D is sufficient to prove the conclusion because it states that the monkeys' social behavior is never determined by genetics; however, its' not necessary for the argument to assume that all social behaviors are independent of genetics. We simply just need to know that some behaviors are independent. Thus, D is too strong to be necessary.

B's negation says, "New patterns of behavior that emerge in macaque populations over the course of a few years or decades are necessarily genetically predetermined." This negation wrecks the argument because it's stating that the new behavior is for sure determined by genetics. Thus, B in its original form is necessary for the argument, so this is the correct answer choice.