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: Echinoderms lack respiratory and excretory systems., Fact2: Echinoderms are represented by the starfish., Question: starfish lack what kind of system? (A) respiratory (B) critical organs (C) alveoli (D) heat or cold (E) hydration (F) Bodily water (G) food and shelter (H) frontal zones
A:
A