A school nursing staff wants to estimate the average weight of girls in the seventh grade as part of the school's Stay Fit program. They measured the weights of 5 girls from each of the 10 seventh-grade classes. The mean of the data was 91 pounds, and the median was 87 pounds. Which prediction matches the data?

A. About one-half of the girls weigh more than 91 pounds.
B. The average weight of the girls is 87 pounds.
C. About one-half of the girls weigh more than 87 pounds.
D. The average weight of the girls is 91 pounds.