Some psychologists believe that, while practice is extremely important, there is a component of intellectual ability that helps determine whether someone will be good at something such as playing the piano. Psychologists David Hambrick and Elizabeth Meinz did a study in the journal Current Directions in Psychological Science on "working memory capacity." It is a core part of the overall intellectual ability and it can predict success in something like playing an instrument. They measured the sight-reading ability of pianists, which is the ability to successfully play a piece of music they have never seen before. They studied two pianists who had accumulated the same number of practice hours but had different levels of working memory capacity. The pianist with the higher working memory capacity performed better on the sight-reading task.

Why did the author include this selection?

A
to introduce the idea that there is a scientific argument about musical talent vs. intensive practicing
B
to elaborate on the idea that most people avoid doing things that they don't think they're good at
C
to develop the idea that innate talent may have an impact on musical ability
D
to defend the idea that dedicated practice is more important than natural musical talent