Given the task definition, example input & output, solve the new input case.
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").
Example: Fact1: a plant requires sunlight to grow, Fact2: Plants to avoid are fast-growing vines that can take over an area in no time., Question: What requires sunlight in order to take over an area? (A) spores (B) fish (C) plants (D) humans (E) pods (F) Oak (G) opossums (H) coral
Output: C
This is a good example. Based on the facts plants require sunlight in order to take over an area.

New input case for you: Fact1: Cells have multiple repair mechanisms to fix mutations in DNA., Fact2: And if the damaged DNA is duplicated, it causes mutation., Question: Cells have multiple repair mechanisms to fix what? (A) a tree falling (B) direct damage to the lungs (C) that material's properties (D) damaged DNA duplication (E) an area swollen with pus (F) Veins and arteries. (G) the body's largest organ (H) The bending of a ray of light
Output:
D