In an Experiment Aimed at Evaluating the Effect of a Memory-Enhancing

Multiple Choice

In an experiment aimed at evaluating the effect of a memory-enhancing drug on the recall of a previously learned response. Either the drug or a placebo was administered to different groups of rats before the memory test. There were three trials of the memory test, and the dependent variable was the time it took the animal to make the correct response.
Suppose the analysis reveals a significant drug by trial interaction. What would we conclude about the effect of the drug on memory?

A) The effect of the delay is different for the drug and the placebo.
B) The drug has no effect on memory.
C) The trials have no affect on memory.
D) No conclusion can be reached without looking at the percent correct responses.