Which one of the following choices is a known factor that influences flexibility?
a. race and ethnicity
b. body composition
c. degree of self-confidence
d. amount of rest

The answer is letter B.

Body composition directly affects flexibility because of the structure of the joints, ligaments, tendons, muscles, fat, and skin that are traits inherited from a person’s set of parents. Generally women are more flexible than men because of their higher fat concentrations and mainly because of their ability to experience pregnancy where bones expand and relax to give way for the baby. Other factors that affect flexibility are body temperature, activity level, and age. Some people are naturally-born flexible but through the right amount of practice it can also be achieved.