GRE Reading Comprehension: Maggoosh-GRE阅读Maggoosh - ED567Y12ZASFP542M

The author considers Gall's methodology to be unscientific for which of the following reasons? A. Gall did not test his assumptions by examining actual brains. B. Gall only based his assumptions on the surface of the skull. C. Gall's conception of validity differed from a contemporary understanding of validity.