In Terms of Explaining Why Exercise Improves Mental Health, One

In terms of explaining why exercise improves mental health, one idea is that as a person engages in exercise and experiences fitness gains or bodily changes

A) self-efficacy remains the same but self-esteem increases.
B) personality changes and results in enhanced mood.
C) self-awareness increases.
D) self-efficacy for exercise increases, and the person experiences a feeling of accomplishment.