Question ID:PT48 S4 Q9 Passage:A recent study of several hundred female physicians showed that their tendency to develop coronary disease was inversely proportional to their dietary intake of two vitamins, folate and B6. The researchers concluded that folate and B6 inhibit the development of heart disease in women. Stem:Which one of the following would, if true, most weaken the researchers' conclusion? Correct Answer Choice:AChoice A:The foods that contain significant amounts of the vitamins folate and B6 also contain significant amounts of nonvitamin nutrients that inhibit heart disease. Choice B:It is very unlikely that a chemical compound would inhibit coronary disease in women but not in men. Choice C:Physicians are more likely than nonphysicians to know a great deal about the link between diet and health. Choice D:The physicians in the study had not been screened in advance to ensure that none had preexisting heart conditions. Choice E:The vitamins folate and B6 are present only in very small amounts in most foods.