Final answer:
The independent variable in the hypothesis by Professor Gummi is 'e. International travel experience.' This variable is manipulated to assess its impact on the dependent variable, which is the academic performance in advanced sociology classes.
Step-by-step explanation:
The independent variable in Professor Gummi's hypothesis, which posits that traveling outside of one's own home country increases students' chances of doing well in advanced sociology classes, is e. International travel experience. An independent variable is the one that is manipulated or changed in a study to see what effect it has on the dependent variable. In this case, the independent variable is the international travel experience, and the dependent variable would be the students' academic performance in advanced sociology classes.
For example, in Frances Heussenstamm’s experiment on police prejudice, putting a Black Panther bumper sticker on students' cars (the independent variable) was hypothesized to affect how often they were stopped by the police (the dependent variable). Similar to this study, Professor Gummi would need to see if the act of international travel (independent variable) has an effect on the sociology class performance (dependent variable).