Which is a personal reason for using tobacco?

weight loss
peer pressure
family use
celebrity use

Peer pressure is the personal reason for using tobacco.  

Explanation:

Personal factors predispose and triggers a person to cultivate risky smoking habits.

Peer pressure due to need for acceptance by the peer group is the main reason for smoking among adolescents.

Peer influence attracts many adolescents into smoking tobacco. The fear of not being accepted by peers or friends if not smoking, or the grandiose feeling of smoking, the attraction of smoking by other peer members leads an individual to smoke.

Some might even be influenced by some family members or celebrity smoking.