In this question, every cups will be filled with 4 ounces yogurt. That mean, the lowest possible of the cups weight would be 4 ounces. After that the customer can the topping without exceeding 6 ounces of total weight. Since it total weight, that means from the 6 ounces there should be 4 ounces of yogurt. Then the maximum weight is 6 ounces
Minimum weight is 4 ounces and maximum weight is 6 ounces, so the answer would be 4,5,6 or any number between 4-6