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").

Fact1: Thyroid hormones increase the rate of metabolism in cells throughout the body., Fact2: Thyroxine, a thyroid hormone, is an aryl iodide., Question: Thyroxine increases the rate of metabolism in cells throughout the what? (A) Summer (B) body (C) state (D) skin (E) H 2 O (F) HIV (G) life (H) humans
B