Both the researchers and the participants in a memory study are ignorant about which participants have actually received a potentially memory-enhancing drug and which have received a placebo. This investigation involves the use of:.
a. random sampling
b. double blind procedure
c. replication
d. hindsight bias

Double blind procedure

Explanation:

Both the researchers and the participants in a memory study are ignorant about which participants have actually received a potentially memory- enhancing drug and which have received a placebo. This investigation involves the use of double blind procedure.

A double blind procedure is an experimental procedure in which neither the subjects of the experiment nor the persons administering the experiment know the critical aspects of the experiment. Both the researchers and the participants in a memory study are ignorant about which participants have actually received a potentially memory- enhancing drug and which have received a placebo so the double blind procedure is important when testing a specific medication or new drugs.

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