Your company needs to create an advertising campaign to generate awareness for a new product. To guide your decision, you run an ad recall experiment: control participants view ad version A and then answer questions about ad A; treatment participants view ad version B and then answer questions about ad B. Both groups answer the same set of questions. You prepare every participant by notifying them of the quiz at the very beginning of the experiment (i.e., before viewing the ad).

1. Identify and explain anyvalidity threats that would negatively impact the results of your experiment.