Answer: C. Your study does not have a control group.
Step-by-step explanation:
In the experimental setup certain number of variables and the groups are required to be considered to conduct the experiment. The independent variable is the variable which can be changed so as to observe such a change over the dependent variable. The dependent variable can be observed due to the changes occurring in the independent variable. The control group is the one which can be used as a standard benchmark for the comparison with the variables.
The given study does not include a control group as both the groups are offered with an activity along with the bowl of candy. No group was left without any activity along with the candy bowl which can indicate that the given study does not include a control group.