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").

[EX Q]: Fact1: Cancer is a disease in which cells divide out of control., Fact2: Cancer is also caused by a mutation., Question: What can mutations lead to in which cells divide out of control? (A) Smoking (B) resistance (C) a disease (D) viruses (E) AIDS (F) bacteria (G) Leptospirosis (H) cigarettes
[EX A]: C

[EX Q]: Fact1: Biodiversity increases the productivity and stability of ecosystems., Fact2: An ecosystem includes the organisms and their habitat., Question: what does biodiversity increase the productivity and stability of? (A) density (B) the looseness of soil (C) water vapor (D) the environment (E) h2o (F) swamp vegetation (G) biological diversity (H) organisms and their habitat
[EX A]: H

[EX Q]: Fact1: operating an automobile usually requires fossil fuels, Fact2: Fossil fuels are a finite resource., Question: What powers most automobiles?  (A) Sunlight. (B) A finite resource. (C) Natural gas. (D) an engine (E) energy of moving objects (F) Water (G) a hydraulic system (H) transportation technology
[EX A]:
B