Instructions: 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").
Input: Fact1: Passive immunity lasts only as long as the antibodies survive in body fluids., Fact2: Booster shots are needed periodically to build up the passive immunity again., Question: What are needed after antibodies won't survive in body fluids? (A) booster shots (B) Veins and arteries. (C) chicken pox (D) Energy. (E) gun shots (F) kinetic energy (G) diseased tissue (H) turn to a doctor
Output:
A