Carrie Was Getting Less Sleep During Midterms So She Began

Multiple Choice

Carrie was getting less sleep during midterms so she began drinking one cup of coffee in the morning to feel more alert. By the end of the semester, Carrie was drinking three cups of coffee each morning to get the same sense of alertness. What has happened to Carrie?

A) She is experiencing tolerance to coffee.
B) Her nervous system is increasing her body's response to coffee.
C) She is experiencing withdrawal when she drinks coffee.
D) She will no longer crave coffee because its effects are diminished.