A market research group wants to find out which of two brands of shoes causes blisters more often. They are considering three methods of gathering data: Method A: Randomly choose 100 people. Ask them...

Extracted text: A market research group wants to find out which of two brands of shoes causes blisters more often. They are considering three methods of gathering data: Method A: Randomly choose 100 people. Ask them what shoes they typically wear and how often they tend to get blisters. Method B: Randomly choose 50 people to wear one brand of shoes and another 50 to wear the other brand. Compare the number of blisters that each group gets over the course of a month. Method C: Find a group of 50 people that own the first brand of shoes, and another 50 people that own the second brand. Monitor how many blisters each group gets. Tell whether each method of gathering data is a survey, an observational study, or an experiment. Which option would give the most reliable results?