Harrison et al. are conducting a study assessing the ability of depressed versus non-depressed participants to remember negative emotions in a short story about a family whose car breaks down. They plan to ask participants to read the story and then make a list of the emotions expressed in the story. Before beginning the study, they make a list of negative emotions (e.g., sadness and anger) that they will record from the participants’ responses. In this example, negative emotions are the ________.
a. independent variable
b. significant variable
c. operational definition
d. dependent variable

The variable of interest is also known as response variable or dependent variable, and in order to find a estimation or this variable we use the predictors, or independent variables.

The dependent variable is known as the variable of interest or "Y" and usually the independent variables are expressed by "X".

The independent variable is the variable that allows to predict the dependent variable.

So for this case we are interested in find the negative emotions for a number of participants taking in count one level with two factors. The Level is frame of mind and the factors are Depressed and Non depressed who represent the independent variable for this case.