Strayer, Drews, and Johnston (2003) had participants in a study follow a pace car in front of them in a driving simulator. Half of the participants found themselves driving in heavy stop-and-go traffic in the simulator, while the other half were in the same situation in lighter traffic. Strayer and his colleagues measured how quickly each participant was able to apply the brakes when the car in

front of them stopped under two different conditions that formed the within-subjects variable: When they were involved in a cell phone conversation on an interesting topic and when they were not on the telephone. The design of this experiment was

a. one variable within-subjects
b. one variable between-subjects
c. within-subjects factorial design
d. mixed factorial design

d