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: when metal conducts heat , that metal expands, Fact2: Conduction is the passing of heat through a medium., Question: What is the result of imperfect passing of heat through a metal, on that metal? (A) contamination (B) expansion (C) sweating (D) Energy. (E) forces (F) burning (G) Evaporation (H) electricity
A:
B