【单选题】Caffeine, the stimulant in coffee, has been called “the most widely used psychoactive substance on Earth .” Synder, Daly and Bruns have recently proposed that caffeine affects behavior. by countering ...
A.
discuss a plan for investigation of a phenomenon that is not yet fully understood
B.
present two explanations of a phenomenon and reconcile the differences between them
C.
summarize two theories and suggest a third theory that overcomes the problems encountered in the first two
D.
describe an alternative hypothesis and provide evidence and arguments that support it
E.
challenge the validity of a theory by exposing the inconsistencies and contradictions in it