In prenatal development, the heart tissue forms before the arms. This pattern of prenatal development is described as

The most effective treatment for obsessive-compulsive disorder is

a. the use of serotonin agonist drugs. b. self-medication using alcohol and cocaine. c. neurosurgery. d. long-term psychotherapy. e. antibiotic drug therapy.

Laura works at a local shelter for teens who cannot remain in their homes, but are not wards of the court. She showed them an extraordinary documentary on homeless teens that featured two who actually testify to Congress about the need for services, and they became much more hopeful about their own futures. She is sharing this with Beatrice, a friend in another city who also works with high risk

teens. Beatrice is a bit more cautious, and decides to randomly create two groups of teens at her facility. She shows one group the inspirational documentary, while the other group simply goes about their usual activities. After the treatment group has viewed the documentary, she has both groups of teens complete the instrument assessing how positively they view their futures. This is an example of a(n) ____. a. basic pre-post randomized experimental design. b. posttest-only randomized experiment c. double-pretest, single-group design created by expanding across time. d. pretest-posttest nonequivalent groups quasi-experiment