Recently, the Mozart Effect Was Studied by Jones and Estell

Recently, the Mozart effect was studied by Jones and Estell by dividing high school participants into two groups.The first group listened to Mozart's music and the second group did not.Both groups completed a series of spatial problems tasks.Results showed that the group of participants who listened to Mozart's music had higher scores on the spatial problems tasks.In this example, what is the dependent variable?

A) Mozart's music
B) scores on spatial tasks
C) the researchers
D) none of the above