A Friend Has Heard That by Adding Oat Bran to Her

A friend has heard that by adding oat bran to her diet, she can lower her cholesterol level. What can you tell her about this?

A) Early studies yielded positive claims for oat bran, but later studies have shown that it does not lower cholesterol.
B) Oat bran in breads and muffins can lower cholesterol, but it does not have the same effect in hot or cold cereal.
C) Two to three servings per week of oat bran can help lower cholesterol, but larger amounts cause diarrhea.
D) Oat bran can lower cholesterol, but a large daily serving is needed to have much effect.