In Experiments, Researchers Often Use Random Assignment to Place Participants

In experiments, researchers often use random assignment to place participants in various groups or conditions in their experiments. An alternative to random assignment is to design the study in such a way that each participant:

A) may receive both the independent and dependent variables.
B) is exposed to all conditions in the experiment.
C) is equally likely to end up in any one of the experimental conditions.
D) may be randomly sampled.