D Question 4 3 pts A sports psychologist believes relaxation will improve how well basketball players shoot free throws. To test this, he designs a study in which free throw performance is measured in a total of 20 players. After the initial test of how well the players shoot free throws, half of the players then receive daily relaxation classes for a month, while the other half watch instructional videos on free throw shooting for the same amount of time as the relaxation classes. Both samples were then tested again after a month of relaxation or videos to measure their free throw performance a second time. For this study, what is the dependent variable (D.V.)? O free throw shooting videos O relaxation techniques O length of time watching videos free throw shooting performance