Research Indicates That Exercise May Be a Useful Resource for Combating

Research indicates that exercise may be a useful resource for combating the adverse effects of stress. Your text suggests this may be because exercise

A) decreases exogenous opioids.
B) increases endorphin levels, thus masking the effects of stress.
C) appears to suppress the immune system.
D) always increases cognitive processes.
E) appears to modulate immune activity during stress.