Given the task definition and input, reply with output. 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: Passive immunity lasts only as long as the antibodies survive in body fluids., Fact2: Furthermore, antibody levels decrease with time., Question: Passive immunity decreases with (A) ozone depletion (B) edema (C) passive-aggressive behavior (D) stellar implosion (E) stress (F) HIV (G) time (H) death
G