Medical research has established that the Beta Diet is healthier than a more conventional diet. But on average, people who have followed the Beta Diet for several decades are much more likely to be in poor health than are people whose diet is more conventional. Which one of the following, if true, most helps to resolve the apparent conflict between the two statements above? ['Recent research has shown that a diet high in fruits, vegetables, and skim milk is even healthier than the Beta Diet.', 'The Beta Diet is used primarily as a treatment for a condition that adversely affects overall health.', 'The Beta Diet provides dramatic health benefits for some people but only minor benefits for others.', 'On average, people who have followed the Beta Diet for their entire lives are much more likely to have a variety of healthful habits than are people whose diet is more conventional.']