Random assignment of participants to the various groups in an experiment
A) makes it more likely that extraneous variables will impact the experiment.
B) increases the probability that the groups are equivalent.
C) is essential if you want to generalize your results to the population.
D) is very difficult to do and is therefore not commonly done.

Question

Quizplus · Accepted Answer

Random assignment increases the likelihood that the groups will be equivalent at the start of the experiment, thereby controlling for extraneous variables and making it easier to attribute any differences in outcomes to the experimental manipulation rather than to pre-existing differences between the groups.

Random Assignment of Participants to the Various Groups in an Experiment