Explain the Completely Randomized Design

Multiple Choice

Explain the Completely Randomized Design
-A drug company wanted to test a new depression medication. The researchers found 600 adults aged 25-35 and randomly assigned them to two groups. The first group received the new drug, while the second received a placebo. After one month of treatment, the percentage of each group whose depression symptoms decreased was recorded and compared. What is the response variable in this experiment

A) the percentage who had decreased depression symptoms
B) the type of drug (medication or placebo)
C) the 600 adults aged 25-35
D) the one month treatment time