Advertising tends to have a greater influence on consumer preferences regarding brands of yogurt than it does on consumer preferences regarding brands of milk. Yet, since the LargeCo supermarket chain began advertising its store-brand products, sales of its storebrand milk increased more than sales of its store-brand yogurt. Which one of the following, if true, most helps to resolve the apparent discrepancy described above? ["Shoppers at LargeCo tend to purchase the chain's own brand of dairy products more frequently than other brands of dairy products.", 'Consumers tend to purchase store brands of yogurt, but purchase whichever brand of milk is least expensive.', 'Supermarkets throughout the entire nation have experienced a sharp decrease in sales of yogurt recently.', 'The typical shopper going to LargeCo for the purpose of buying milk does not go with the intention of also buying yogurt.']