max is testing how caffeine affects test scores. what might be a constant in this experiment?\nthe type of…

max is testing how caffeine affects test scores. what might be a constant in this experiment?\nthe type of test the subjects are taking\nthe subjects favorite foods\nthe eye color of the subjects\nall of these
Answer
Brief Explanations:
In an experiment testing how caffeine affects test - scores, variables like favorite foods and eye color are irrelevant to the relationship between caffeine and test - scores. Also, to accurately measure the impact of caffeine on scores, the type of test should remain the same. So all these can be constants.
Answer:
D. All of these