单选题
In a recent advertisement, a major cereal company contended that the better educated people are, the more likely it is that as children they regularly ate oatmeal. As evidence, the company cited a national random survey of college graduates in which four-fifths of all those surveyed reported having eaten oatmeal at least once a week when they were young. Which one of the following is an additional piece of information that would support the cereal company's conclusion?