Dr. Gruber conducts a study in her laboratory whereby she measures the body language of heterosexual ...

Dr. Gruber conducts a study in her laboratory whereby she measures the body language of heterosexual males in the presence of a group of same sex or opposite sex people.
 
  Dr. Gruber concludes that males express more types of body language when around females as a way to attract the opposite sex. Frank, a college student who participated in the study and behaved in the predicted way in Dr. Gruber's study, is out at a night club. When surrounded by a group of female students he feels tense and remains motionless. However, when a group of his male friends arrive Frank relaxes and shows increased signs of body language. Frank's behavior outside of the laboratory seems to contradict Dr. Gruber's findings. What mistake has Dr. Gruber made in analyzing her results?
 
  a. As a female, she cannot possibly understand the mind of a male college student.
  b. She did not use an appropriate measure of body language.
  c. She did not consider that some of the participants would knowingly deceive her.
  d. She did not consider how real life situations would affect the behavior of males and has over-generalized her laboratory findings.