You Feel Fine as You Sit Down in Your Usual

Multiple Choice

You feel fine as you sit down in your usual seat in German class. However, when Dr. Kraus announces that there will be a pop quiz on the 100 most difficult vocabulary words covered in the last few classes, your heart starts pounding and you get a queasy feeling in your stomach. This reaction is most likely a(n)

A) UCS.
B) UCR.
C) CS.
D) CR.