An Experiment Includes a Treatment Condition, a No-Treatment Control, and a Placebo

Multiple Choice

An experiment includes a treatment condition, a no-treatment control, and a placebo control. Which two conditions should be compared to determine the size of the effect that is actually caused by the treatment?

A) Placebo versus treatment
B) Placebo versus no-treatment
C) Treatment versus no-treatment
D) Placebo control only