A psychologist believes that music affects a person's mood. He has some participants listen to waltzes and others listen to military marches, then measures each participant's mood with a paper-and-pencil test. What are the independent and dependent variables?

The type of music is the independent variable and the participant's mood is the dependent variable.

Explanation:

Independent variable: In research, the independent variable is considered as the variable that is being manipulated or changed by an experimenter while conducting specific research. It is the independent variable which is responsible for affecting the dependent variable during an experiment i. e, any change or alteration in the independent variable causes a direct change in the dependent variable.

Dependent variable: In research, the dependent variable is the variable that is being measured or tested in an experiment by the researcher or experimenter. It carries a direct effect from the independent variable.