Retail stores that are in place for a limited time period and serve partly as public relations efforts and partly as testing grounds are known as what? A. Pop-up stores B. Shopping Simulation C. Style testing D. Showcase storesWhich type of research method asks questions of a group of people that share similar characteristics over time in order to track changes in consumer attitudes and opinions? A. Mall-intercept research B. Cohort study C. Style testing D. Cross-sectional study