Kenzie Is an Infant That Sucks Her Thumb When She

Kenzie is an infant that sucks her thumb when she is anxious. She also chews on toys when she sees other children fighting. As she gets a little older, she will go to her room when her brothers start fighting. Why does Kenzie do all of these behaviors?

A) Kenzie is displaying self-conscious emotions.
B) Kenzie is engaging in emotion mapping.
C) Kenzie is engaging in emotional regulation.
D) Kenzie is engaging in an innate reaction to stress.