Manul s are small, shy felines. They live mostly alone in out-of-the-way parts of Africa, such

Choice D is the best answer because it most logically completes the text’s discussion of manul s. The text states that manul s live in "out-of-the-way parts of Africa" (citing the famously remote Mount Everest as an example) and indies that it is difficult to research the s because of the loion of their habitats. By emphasizing that the habitats are remote in relation to humans, the text conveys that being "distant from," or far from, large groups of humans makes manul s challenging to study.

Choice A is incorrect because saying that the habitats of manul s are "full of large populations of humans" would indie that the s cohabitate with many humans, which would directly contradict the text’s claim that the s live in "out-of-the-way" areas. Choice B is incorrect because the missing words describe an aspect of manul s’ habitats, or the areas where they live, and it wouldn’t make sense to say that areas could be "drawn to," or attracted by, large groups of humans. Choice C is incorrect. In this context, "responsible for" would mean either having an obligation to care for something or being the cause of something, and it wouldn’t make sense to say that the habitats of manul s (the areas where the s live) would need to care for humans or that the habitats somehow created large human populations.