An experimental group listened to 10 minutes of a Mozart sonata, a control group listened to 10 minutes of relaxation to instructions, while the other control group listened to silence. The Mozart group performed much better on a subsequent test of spatial abilities than the two control groups. The results of this experiment are not valid because
A)10 minutes is an inadequate amount of time.
B)There could be confounding variables.
C)The amount of time is not indicated for the group who listened to silence.
D)There are two control groups.

Question

Quizplus · Accepted Answer

Confounding variables, which are variables that the researcher failed to control, or eliminate, damaging the internal validity of an experiment, could explain the difference in performance between the groups. These variables could include prior exposure to music, natural differences in spatial abilities, or even the psychological effects of listening to music versus silence or relaxation instructions.

An Experimental Group Listened to 10 Minutes of a Mozart