Final answer:
This scenario is an experiment if there is an independent variable being manipulated to observe its effects on the dependent variable, which is the number of words recalled.
Step-by-step explanation:
An experiment is a research method in which an independent variable is manipulated to determine its effects on a dependent variable. In the context given, this is an experiment if there is an independent variable. The independent variable would be whatever condition or manipulation the experimenter applies to one group and not the other. The dependent variable, in this case, is the number of words remembered from a list, which is what the experimenter measures. If there's no independent variable being manipulated, then it would not constitute a true experiment as there would be no factor to test the impact on memory.