According to the article Over the Hill about the Betula study of adult cognition, cross-sectional studies of memory might be most likely to suffer from a classic confound resulting from:

ERP and fMRI measures of brain activity indicate that second-language processing is

A) more lateralized, and also overlaps more with brain areas devoted to first-language processing, in older than in younger learners. B) less lateralized, and also overlaps less with brain areas devoted to first-language processing, in older than in younger learners. C) better developed in adults who take language classes than in young children who immigrated to the United States in infancy. D) shared between the left and right hemispheres of the brain, whereas first-language processing is primarily located in the right hemisphere.

The case study is useful for:

a. studying rare phenomena. b. suggesting new hypotheses. c. studying brain damage. d. all of these