In Terms of Human Capital, Which of the Following Is

In terms of human capital, which of the following is the best example of an inherited skill?

A) a neurosurgeon who can perform brain surgery after many years of training
B) a salesman doubles his sales after taking a training course
C) a worker who exercises is healthier and therefore more productive
D) a retail worker who is able to work overtime each week
E) a music teacher who can carry a tune for the school choir