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").

[Q]: Fact1: Air pollution harms the respiratory and circulatory systems., Fact2: Cars are a significant source of air pollution., Question: What harms the respiratory and circulatory systems? (A) oil (B) rain (C) sulfur (D) cars (E) tires (F) coal (G) tar (H) bicycles
[A]: D


[Q]: Fact1: Carbon may be stored in sedimentary rock for millions of years., Fact2: Limestone is a type of sedimentary rock., Question: What element can be stored in limestone for millions of years? (A) oxygen (B) Energy (C) matter (D) carbon (E) sodium (F) helium (G) rock salt (H) heat
[A]: D


[Q]: Fact1: Skin color is a polygenic trait., Fact2: Chapter 5 discusses polygenic inheritance and intelligence., Question: What trait is inherited? (A) intelligence (B) weight (C) vision (D) keratin (E) humans (F) canis lupus (G) strength (H) tooth enamel
[A]:
A