An Experiment Conducted by Researchers Involved Adding a Synthesized Female

An experiment conducted by researchers involved adding a synthesized female pheromone to the perfume of one group of women (the experimental group) ,and a placebo was added to another group (the control group) .The researchers found that the women who had pheromone-treated perfume had intercourse more frequently than the control group.
However,the two groups did not differ in their frequency of masturbation.This indicates that

A) the pheromone increased the women's attractiveness to men.
B) the pheromone decreased the women's sex drive.
C) the pheromone reduced the attraction that women felt toward men.
D) the pheromone made women less attractive to men.