A study of students taking Statistics 101 was done. Four hundred students who studied for more than 10 hours averaged a B. Two hundred students who studied for less than 10 hours averaged a C. This difference was significant at the 0.01 level. What does this mean?

A. The probability that the difference was due to chance alone is greater than 0.01.

B. There is less than a 0.01 chance that the first group's grades were better by chance alone.

C. The improvement was due to the fact that more people studied.

D. There is not enough information to make any conclusion.