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: global warming is when worldwide temperature increases, Fact2: Global warming is caused by carbon dioxide trapped in the atmosphere., Question: What does carbon dioxide cause? (A) skateboards (B) Greenhouse gases (C) Worldwide temperature increase (D) major threat to health (E) direct damage to the lungs (F) running (G) a lot of human deaths (H) Temperature decrease
Example Output: C

Example Input: Fact1: when light enters the eye through the pupil , that light falls on the retina, Fact2: Images are retained on the retina of a viewer's eye for a fraction of a second after they strike it., Question: Where are images retained? (A) Retina (B) RNA (C) calcite (D) an object (E) arteries (F) energy (G) squids (H) segmented
Example Output: A

Example Input: Fact1: Some arthropods have special excretory structures., Fact2: Crustaceans are, like insects, arthropods., Question: Crustaceans and insects have what special structures? (A) the eyes (B) a cuticle (C) internal (D) excretory (E) invisible (F) Chlorophyll (G) fur and fat (H) muscled
Example Output:
D