“As you can see by the steps listed above, shooting free throws is more of a mental process than anything else.”

What does the author mean by the phrase, “more of a mental process than anything else.”?
a. Free throws can be mastered by imagining how to shoot them.
b. Through concentration and consistent effort you can successfully shoot free throws.
c. By “visualizing” a successful free throw, you will eliminate the need for practice.
d. None of these are what the author meant.