Portfolio tests:
A.
present a panel of consumers with an ad and ask for their reactions concerning the ad's effectiveness, appeal, etc.
B.
present a panel of consumers with an ad for a limited period of time. The ad is then removed, and the respondents are asked to recall as much pertinent information as possible.
C.
present consumers with a sample of a product and several different advertisements for the product. They are asked to select the one they think is most effective and explain why.
D.
place a test ad in the midst of other ads and stories, instruct consumers to look at the ads and stories, and then ask consumers questions about what was seen.
Answer: D