Which type of variable is used to hold other variables constant to isolate effects?

Which type of variable is used to hold other variables constant to isolate effects?

• A. Independent variable
• B. Dependent variable
• C. Control variable
• D. Moderator variable

Answer: (C)

Holding potential influencing factors constant is essential to isolate the effect of the variable you’re studying. The variable kept constant to prevent other influences from entering the results is the control variable. By holding these factors steady, you reduce confounding so you can attribute observed changes in the outcome to the variable you manipulate. The independent variable is what you change to test its effect, and the dependent variable is what you measure. A moderator variable, instead, alters the strength or direction of that relationship, rather than being kept constant. For example, in a study on how study time affects exam score, you might keep sleep quality, prior knowledge, and study environment constant as control variables to ensure any differences in scores are due to study time.

Holding potential influencing factors constant is essential to isolate the effect of the variable you’re studying. The variable kept constant to prevent other influences from entering the results is the control variable. By holding these factors steady, you reduce confounding so you can attribute observed changes in the outcome to the variable you manipulate. The independent variable is what you change to test its effect, and the dependent variable is what you measure. A moderator variable, instead, alters the strength or direction of that relationship, rather than being kept constant. For example, in a study on how study time affects exam score, you might keep sleep quality, prior knowledge, and study environment constant as control variables to ensure any differences in scores are due to study time.