Answer:
C. the nonmedical or improper use of a drug, which can interfere with a healthy life.
Step-by-step explanation:
Drug abuse takes into consideration the amount and frequency of use of a drug, regardless if it is legal or illegal and how it interferes with a healthy life. Drug abuse can occur with nonmedical or prescribed drug too, what defines drug abuse or misuse is the improper use of it and its consequences, it harms a person, her life and people around her.