In a study to investigate the relationship between age and favorite flavor of ice cream, an equal number of people were randomly selected for each age group. Is the study observational or experimental? If it is an experiment, what is the controlled factor?

Select the correct answer below:

The study is an experiment. The controlled factor is the survey.

The study is an experiment. The controlled factor is ice cream preference.

The study is an experiment. The controlled factor is age.

The study is an observational study.