Many breakfast cereals are fortified with vitamin supplements. Some of these cereals provide 100 percent of the recommended daily requirement of vitamins. Nevertheless, a well-balanced breakfast, including a variety of foods, is a better source of those vitamins than are such fortified breakfast cereals alone. Which of the following, if true, would most strongly support the position above? ['Cereals containing vitamin supplements are no harder to digest than similar cereals without added vitamins.', 'People who regularly eat cereals fortified with vitamin supplements sometimes neglect to eat the foods in which the vitamins occur naturally.', 'Unprocessed cereals are naturally high in several of the vitamins that are usually added to fortified breakfast cereals.', 'In many foods, the natural combination of vitamins with other nutrients makes those vitamins more usable by the body than are vitamins added in vitamin supplements.']