Suppose You Want to Test the Effects of Handing Out

Multiple Choice

Suppose you want to test the effects of handing out free samples of pizza on the sales of frozen pizza in supermarkets. For one week, you provide free samples in a "test" supermarket located in one area and do not provide free samples in a "control" supermarket located in another area. During this period a pizzeria located in the test area goes out of business. If you found that pizza sales increased in the test store but not in the control store, what is a likely alternative explanation to the effect of providing free hot pizza?

A) history effect
B) maturation effect
C) statistical regression
D) pretesting effect
E) testing-treatment interaction effect