From the last paragraph, we learn that envy sometimes stems from ______.

A．he is reluctant to take on family responsibilities
B．he believes that life will be more cheerful if he remains single
C．he finds more fun in dating than in marriage
D．he fears it will put an end to all his fun adventure and excitement

A．Happiness often goes hand in hand with pain.
B．One must know how to attain happiness.
C．It is important to make commitments.
D．It is pain that leads to happiness.