What kind of research has supported the notion that adolescents' moods are less stable than those of adults?

A young woman recovering from a blow to her head finds she has great difficulty maintaining her balance and coordinating her movements. Injury to which part of her brain is likely to be causing her difficulties?

a. cerebellum b. medulla c. cerebral cortex d. thalamus

In general, the validity of the WAIS-IV

a. rests on studies done with earlier versions of the test. b. is undocumented, but promising. c. indicates the WAIS correlates poorly with other tests of intelligence. d. is weak when factor analytic data are considered.