A Fortune 500 company is piloting a new advertisement and would like to determine which main character viewers prefer (an older male vs an older female). So, they took a random sample of 150 US adults aged 18 to 65 and had each of them watch the ad twice, once with the older male as the main character and again with the older female as the main character, randomizing the order in which each person viewed the advertisements. After watching both ads, the participants rated which ad they preferred. What type of experiment is this? A. Matched Pairs B. Completely Randomized C. Randomized Comparative D. Randomized Block E. Observational Study