By age _____, children are quite good at producing complex and grammatically correct sentences

A friend is taking a drug awareness class. One of the things he learns is that LSD, a hallucinogenic drug that produces bizarre sensory experiences, is believed to work because it

a. suppresses the effect of serotonin neurons. b. increases the production of serotonin. c. enhances the effect of serotonin, which is normally excitatory. d. removes serotonin from the body.

Sexual excitement seems to be influenced by the ______

a. limbic system c. upper spinal cord b. parietal lobes d. thyroid gland