The answers are:
A. Having peer pressure. Children will try to fit in with other children by doing what they think is "cool".
B. Coping with problems. Not many people think about it because they think "Oh, they're just kids!" but children have problems too. Abuse, divorces, you name it.
D. Improving relationships with friends. Some people really need friends and will do anything to get one. This includes smoking, too.
