Instructions: 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").
Input: Fact1: Lung cancer is most often caused by exposure to tobacco smoke., Fact2: Tobacco is most commonly smoked in cigarettes., Question: What is lung cancer most often caused by exposure to? (A) Chemical energy (B) carbon dioxide (C) asbestos (D) sunlight (E) water (F) fossil fuels (G) cigarettes (H) hydrocarbons
Output:
G