When He Wakes Up in the Morning,Matthew's Mother Turns on the Overhead

Multiple Choice

When he wakes up in the morning,Matthew's mother turns on the overhead lights in his bedroom.Almost immediately,the ________ in his brain cause(s) a pupillary reaction that leads his pupils to dilate in the bright light.​ 

A) superior colliculi 
B) periaqueductal gray 
C) red nucleus 
D) inferior colliculi