When Sam Walks into His Class,he Does Not Have to Think

Multiple Choice

When Sam walks into his class,he does not have to think consciously about how to walk.When he gets there,he pays attention to the lectures even if they are boring or he is tired.In this scenario,the brain structure that is most likely causing these stereotyped patterns of behavior in Sam is the

A) reticular formation.
B) substantia nigra.
C) hypothalamus.
D) amygdala.