Roberto is an athletic trainer who knows that mental barriers are often the toughest challenge to fitness. He uses a saying to remind his clients that the mind can hinder health just as much as physical limitations. What saying does he MOST likely use to demonstrate this concept? Question 6 options:

A. Whether you think you can or you think you cannot, you are right.

B. It's not about being the best; it's about being better than you were yesterday.

C. The pain you feel today will be the strength you feel tomorrow.