Question

what is one reason it may be harder for one person than another to quit nicotine use?
genetics
peer pressure
weight gain
celebrity use

Explanation:

Genetics can influence an individual's response to nicotine, including factors like metabolism of nicotine and susceptibility to addiction. Peer pressure, weight gain, and celebrity use are more external or behavioral factors rather than inherent biological ones that directly affect the physiological aspect of quitting nicotine as genetics does.

Answer:

genetics