In general, as children become adolescents, their feelings of competence

Researchers turn to correlational studies when

a. large groups of participants are involved. b. they are certain that participants can remember accurately what happened to them earlier. c. variables of interest cannot be altered by the researchers. d. communication with participants may be a problem. e. their hypotheses are causal in nature.

Jill who is 10 repeatedly surfs the Internet late at night although her parents have forbidden

her to do so. She waits until they are asleep and then sneaks onto the computer. She sends threatening messages to other girls in her class and has spread damaging rumors on the Internet about her classmates. When confrontedabout this behavior, Jill becomes hostile and destroys her stuffed animals. Which one of the following diagnoses best fits Jill's behaviors? a. Childhood-onset conduct disorder b. ADHD c. Temper tantrums d. Oppositional defiant disorder