Washington is conducting an experiment in which he is interested in the effects of the drug alprazolam on episodic memory in adult participants.

Dr. Washington is conducting an experiment in which he is interested in the effects of the drug alprazolam on episodic memory in adult participants.  He conducts an experiment in which he gives one group a pill containing 1 mg of the drug and a second group a placebo pill.  One hour following drug administration he has the participants study 50 words, one a time, and then asks them to recall as many of the words as possible.  What is Dr. Washington’s independent variable? (Points : 1) Drug dosageEpisodic memoryThe 50 study wordsPerformance on the free recall task