In a study on the effects of caffeine on memory, participants drank a bottle of tasteless water containing 100, 50, or 0 milligrams of caffeine. Neither the researcher who handed out the bottled water nor the study participants knew whether the water contained caffeine or not. This is an example of a study.

A double-blind study

Explanation:A double-blind study occurs when an experiment is carried out in a way that neither the experimenter nor the participants know what kind of treatment they are recieving. This is crucial in order to eliminate bias results from that experiment. This research bias may be due to the placebo effect(this is an effect caused by a non drug or non medical substance such as a sugar pill) .

option c

explanation:

strive for superiority

the above statement/question is (true);