The of behavior rule states that a target behavior should only be selected when it can be determined that the behavior will produce natural reinforcement.

a. funcitonality
b. valdity
c. relevance
d. importance

C) Relevance

Explanation:

The relevance of behavioral rules states that target should be on some specific behaviors.

The behaviors helps to create reinforcement in a natural manner.

The behavior becomes the natural working process of the body, therefore we should target that behavior which is creating a weak link within an individual so as to improve have upon and strengthen it.

the answer to your question is,

d. when a child was born.

-mabel < 3

answer; english speaking;