When a number of genes make small contributions to a trait, this is known as mixed dominance

Field studies of long-term viewing of violence on television suggest that

a. it would be prudent to have children who watch television violence engage in vigorous physical activity to discharge their violent feelings. b. the more closely violent television situations resemble the child's actual environment, the greater their effect will be. c. young children are more vulnerable than older children to the effects of television violence. d. long-term viewing appears to increase aggressive behavior, but the evidence is not conclusive. e. long-term viewing causes aggressive behavior among boys but not among girls.

Which of the following is necessary for a diagnosis of obsessive-compulsive disorder?

A. The presence of compulsive behaviors B. A persistent awareness of the irrational nature of the obsessions experienced C. Evidence of psychosis D. The symptomatic behavior causes distress.