Recent research indicates that an unknown number of youths experiment with drugs but do not continue with regular use. this process is called:

The process in which youths experiment with drugs but do not continue with regular use is called experimental use.

Explanation:

Experimental use of drugs is strongly related to curiosity. It represents the first stage of substance abuse and it tends to last shortly.  Teenagers and young individuals usually incur in this practice looking for social acceptance, commonly called "fit it" your group of peers.

so we know the answer cannot be c because no insect or animal starts as an adult

the answer is a. a swimming larvae

because since they are sea animals they automatticaly have to know how to swim they cannot just sink to the bottom

sorry if this is the incorrect answer.

hpv is the answer