At the Rodriguez Advertising agency's market research department, the researchers are testing the reactions to a new ad for a new flavor of ice creamjungle crunch. The researchers measure the ad's impact on a viewer using the mouse or hand-dial procedures intended to capture moment-by-moment processing. In an ad copy test, viewers are asked to use their mouse (or given a dial that turns to the left or right) to indicate reactions while continually viewing the ad. Turning it to the left means "I hate this," and turning to the right indicates "I think this is great." This idea is useful in editing ineffectual sections of an ad and in identifying which positive sections might be played up. What is the main problem with this evaluation method? a. Measures taken at a particular moment are better predictors of liking for brands. b. Accumulating the responses over the whole ad are better predictors of liking for brands than those taken at any particular moment. c. Measures taken after the ad are better predictors of liking for ads than those taken at any particular moment. d. Critics say that viewers' reactions to an ad have a natural lag