You will be given a definition of a task first, then some input of the task.
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").

Fact1: Antigens are found on cancer cells and the cells of transplanted organs., Fact2: Antigens are proteins foreign to the body., Question: proteins foreign to the body can be found where? (A) in the lymph nodes (B) in nerve cells (C) in the kidneys (D) on cancer cells (E) critical organs (F) mouth of rivers (G) Earth orbiting the Sun (H) the skin
Output:
D