Random assignment is important in experiments because: group of answer choices
a. it eliminates experimenter expectancy effects.
b. it ensures that the samples are representative of the population.
c. it magnifies the validity of the operational definitions used in the study.
d. it balances differences between participants across experimental groups.

D. it balances differences between participants across experimental groups.

Step-by-step explanation:

A. it eliminates experimenter expectancy effects.

this is the effect of random sampling

B. it ensures that the samples are representative of the population.

this needs minimum sample size and random sampling

C. it magnifies the validity of the operational definitions used in the study.

Not true, doesn't magnify the validity

D. it balances differences between participants across experimental groups.

True