Answer:
Option C) Whether or not a subject attends preschool
Step-by-step explanation:
We are given the following information in the question:
Students were divided into two groups, one group will attend preschool program, the second group will not attend preschool.
The researcher plans to observe whether or not they graduate from high school.
Explanatory Variable:
Thus, the explanatory variable in the above situation is
Option C) Whether or not a subject attends preschool