In a recent study, sedentary middle-aged men who drink more than two cups of coffee a day were found more likely than other sedentary middle-aged men to have a high blood level of cholesterol, which is a factor increasing risk of heart disease. Cholesterol can reach the blood from food and drink but is not contained in coffee.
Which of the following, if true, most seriously weakens a conclusion from the study that for sedentary middle-aged men coffee increases the risk of heart attack
A．A sedentary style of life increases levels of cholesterol in the blood.
B．Coffee contains caffeine, which acts as a stimulant that increases heart rate.
C．The men studied drank their coffee without milk or cream, which contain cholesterol.
D．In both groups, the men were likely to be overweight, and excess weight is a factor that increases risk of heart diseases.
E．(E) The men who drank more than two cups of coffee a day also ate more foods high in cholesterol.