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 Input: Fact1: tidal energy can be used to produce electricity, Fact2: Tidal caves are formed by the energy of the rising and falling tides., Question: what can produce electricity? (A) rivers (B) animal transport (C) tidal caves (D) Nematoda (E) rays or beams (F) animals (G) cactuses (H) photons
Example Output: C

Example Input: Fact1: Pneumonia may be caused by an infection or injury of the lungs., Fact2: Lung injuries are treated with bronchodilatory treatment., Question: What treatment can be used in treating pneumonia? (A) the respiratory system (B) a breathing mask (C) bronchodilatory treatment (D) aqueous solution (E) immunotherapy (F) radiation therapy (G) immune system (H) chemotherapy
Example Output: C

Example Input: Fact1: Biodiversity increases the productivity and stability of ecosystems., Fact2: Biodiversity is basically genetic diversity., Question: What increases the productivity and stability of ecosystems? (A) Fully cooking the oysters (B) genetic uniformity (C) genetic diversity (D) extinction (E) agriculture (F) disease (G) Earth orbiting the Sun (H) recycling
Example Output:
C