Error in audio version on General Pool

Notice: There is an error in our audio version of the General Class question pool.

G7B04 - Which of the following describes the function of a two input NOR gate. The reader gives the answer as: C – output is low when either or both inputs are low. That answer is not even a choice on the possible answers. The question from the FCC question pool is below.  

G7B04 (C) Which of the following describes the function of a two input NOR gate?
A. Output is high when either or both inputs are low
B. Output is high only when both inputs are high
C. Output is low when either or both inputs are high
D. Output is low only when both inputs are high