Researchers studying the effects of caffeine tested the reaction times of women who first drank either a beverage with caffeine or a decaffeinated version of the same beverage.In this study, the reaction time of each participant would be:

Question

Quizplus · Accepted Answer

The dependent variable is the variable being measured and tested by the researchers, which in this case would be the reaction time of the participants. The independent variable is the variable being manipulated by the researchers, which would be whether or not the participants consumed caffeine. A placebo is a substance or treatment that has no therapeutic effect but is given to participants in order to deceive them into believing they are receiving actual treatment. A confounding variable is an extraneous variable that is not the independent or dependent variable, but can still affect the results of the study. Therefore, the best choice is D.

Researchers Studying the Effects of Caffeine Tested the Reaction Times