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 Input:
Fact1: a black hole is formed by a high-mass star collapses, Fact2: Black Holes Black holes are the inevitable conclusion of Einstein's General Theory of Relativity., Question: When do stars fulfill the inevitable conclusion of Einstein's General Theory of Relativity? (A) inactive (B) Winter (C) an object (D) observe it (E) collapse (F) light (G) our star (H) ligt

Ex Output:
E

Ex Input:
Fact1: threatening behavior by predators causes a porcupine to extend its quills, Fact2: Puffers are smooth skinned while Porcupines have the characteristic spines or quills., Question: What does a porcupine do with its spines when it's threatened? (A) killing insects (B) Shoot them (C) kill them (D) protect them (E) Extend them (F) Shed them (G) Retract them (H) behave

Ex Output:
E

Ex Input:
Fact1: when a metal rusts , that metal becomes orange on the surface, Fact2: Iron rusts in the presence of oxygen and water., Question: Exposure to oxygen and water can cause iron to (A) decrease strength (B) melt (C) uncontrollable burning (D) thermal expansion (E) turn orange on the surface (F) vibrate (G) Extremes of temperature (H) levitate

Ex Output:
E