Let's go through paragraph by paragraph to figure this one out. The first paragraph sets up the issue at hand by opening with a discussion of super performers. The main point of the next paragraph is to tell us that recent research actually suggests that exceptional performance stems from acquired skills and adaptations, not innate abilities. The paragraph after expands on this thought, and the last paragraph ends up concluding the previous ones. The answer choice that best encapsulates these ideas is (D).
(B) is incorrect because it is slightly too strong. The author is not claiming that "anyone" can achieve exceptional levels of performance with sustained intense practice and training. No matter how much, for example, someone born blind may train, she will likely never be a world class soccer player (setting aside potential technologies that would aid her). Hope this helps!
