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: most canyons are formed by flowing rivers through erosion over long periods of time, Fact2: Canyon formed as a consequence of river erosion., Question: what does erosion form? (A) valleys (B) Sediment (C) mountains (D) canyons (E) soils (F) hills (G) soft soil (H) loose soil
Example Output: D

Example Input: Fact1: rain causes erosion, Fact2: Erosion of dunes leads to erosion of the beach and of the Island., Question: What can destroy dunes? (A) wind (B) fire (C) turtles (D) storms (E) clams (F) heat (G) rain (H) grain
Example Output: G

Example Input: Fact1: Biomass is the total mass of organisms at a trophic level., Fact2: Most living things are called organisms., Question: Biomass is the total mass of living things at each what? (A) trophic level (B) important habitats (C) Energy. (D) food and shelter (E) Power plants (F) animals (G) body water (H) heat energy
Example Output:
A