Mood disorders have been correlated with

Your next-door neighbors are going crazy. They brought their newborn home from the hospital only to find that he cries for long periods of time and do not know what to do about it. What would you tell them?

a. The baby might have diaper rash. b. Many American infants cry frequently for no apparent cause. c. The incessant crying indicates that there is a neurological problem. d. It is because they have a lot to learn as parents, but they will figure it out.

Randomly assigning participants to condition allows the researcher to minimize the effects of

A) demand characteristics. B) the experimental treatments. C) systematic differences between the groups. D) placebos.