While waiting in line to buy a cheeseburger for $2 and a drink for 75 cents, Aaron notices that the restaurant has a value meal containing a cheeseburger, drink, and French fries for $3. For Aaron, the marginal cost of purchasing the French fries: a. cannot be determined because the information about the price of the French fries is not provided. b. would be zero c. would be 50 cents. d. would be 25 cents.