Research Cited in Your Textbook Refutes the Stereotype That Adults

Research cited in your textbook refutes the stereotype that adults in old age are unhappy and states that:

A) Future-oriented planning enhances life satisfaction and the perception of control.
B) Being on a regimen of prescription medication can help older adults feel happier.
C) Engaging in a regular program of physical exercise can help the elderly feel happier.
D) Engaging in some kind of regular volunteer work can help older adults feel happier.