Definition: In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").
Input: Fact1: Bile reduces the acidity of food entering from the highly acidic stomach., Fact2: Bile from the liver contains bile salts and many organic substances but no enzymes., Question: what helps reduce acidity of food entering from the stomach? (A) cilia (B) fumes (C) kinase (D) liver (E) mucus (F) enzymes (G) insulin (H) herbs
Output:
D