Chan Has Been Getting to School Early for a Meeting

Multiple Choice

Chan has been getting to school early for a meeting with his quiz bowl team as they are getting ready to compete. In order to keep up with his schoolwork, he has been on his laptop later and later in the evening. Even when he is finished, it seems to take his body more time to become sleepy even though he is tired throughout much of the day. This didn't happen when he was in elementary school, even when he went to before school practices. Chan is most likely experiencing the ______.

A) fight or flight response
B) HPG axis
C) secular trend
D) delayed phase preference