A group of researchers wants to determine if people are more likely to follow directions if the person giving the directions is wearing a uniform. Half the participants are directed to a parking spot by a uniformed security guard, the other half are directed to a parking spot by an individual wearing blue jeans and a t-shirt. In this study, the dependent variable would be
a. the number of participants who park in the spot they are directed to.
b. the type of clothing worn by the person giving the directions.
c. the gender of the person driving into the parking lot.
d. the distance between the parking spot and the entrance.