Answer:
INTERNAL:
Some teens may use Narcotics due to depression or anxiety, narcotics may be the only way they think they can “escape” it. A reason a teen might choose not to use is that they have self morals that are against using drugs/narcotics.
EXTERNAL:
Some teens may use narcotics due to peer pressure or troubled home issues (divorced parents, abusive parents, etc.). Some teens may choose not to use narcotics because they’re parents are very strict and they will punish the teen or the teen has friends telling them not to use drugs/narcotics.
I really hope this helps!! :)