题目选项分析

Phytonutrients, found in fresh fruits and vegetables, have beneficial effects on the human cardiovascular system. Because heart disease is a major health concern, American doctors should encourage all people, especially those with heart disease, to eat a diet high in fresh fruits and vegetables.

Which of the following, if true, provides the most support for the argument above?

【选项】vegetarians tend to live longer than folks in the general population