An Important Role of the Exchange System of Categorizing Foods

An important role of the exchange system of categorizing foods is to:

A) provide food lists for people who want an exact match on all nutrients in a food category.
B) provide groupings of foods with similar carbohydrate, fat, protein, and calorie contents.
C) calculate the exact number of calories provided by a person's diet.
D) have foods available from one group to substitute for foods not liked in another group.