"In Our Research,we Are Looking at How Gender (Male or Female)affects

"In our research,we are looking at how gender (male or female) affects the amount of money individuals leave for tips at restaurants." A possible hypothesis based on this research question is

A) men are more likely to be large tippers than women.
B) women are more likely to be large tippers than men.
C) large tippers are more likely to be physically attracted to restaurant workers of the opposite sex.
D) all of these are plausible hypotheses.
E) none of these are plausible hypotheses.