For Questions 17 and 18, identify whether the variable described is an independent variable or a dependent variable for an experiment. Answer I for an independent variable and D for a dependent variable.

Suppose a researcher records differences in cell phone use during class between students who are in lower-level classes and advanced classes. What is the quasi-independent variable in this example?

a. cell phone use

b. class level (lower-level, advanced)

c. the college where students were observed