Mrs. Myles gave the same test to both her first and third-period class. In the first period, the mean was 75 and the range was 30. In the third period, the mean was 85 and the range was 50.

Which is a true statement?

A) Most of the third period scored in the '80s.

B) More people had a score in the 70's in the first period.

C) On average, the third period did better than the first period.

D) On average, the first period did better than the third period.