Who Has the Most Accurate Opinion About Gender Differences in Math

Who has the most accurate opinion about gender differences in math skills?

A) Rosie, who thinks that boys usually get better grades than girls in high school math courses
B) Opal, who thinks that in elementary school, girls are better than boys in math computation
C) Sally, who thinks that girls are better than boys in math problem solving at all ages
D) Gerald, who think that boys are better than girls in all areas of math at all ages