Detailed 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").
Q: Fact1: Plasma cells are activated B cells that secrete antibodies., Fact2: Antibodies are produced by plasma cells., Question: What secrete antibodies? (A) parasites (B) barnacles (C) the body's largest organ (D) major threat to health (E) activated b cells (F) resistance activities (G) fur seals (H) it keeps an organism warm
A:
E