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: Zooplankton are tiny animals that feed on phytoplankton., Fact2: Planktonic plants are called phytoplankton., Question: what do zooplankton feed on? (A) planktonic plants (B) Chemical energy (C) animals (D) microorganisms (E) NaCl (F) Chlorophyll (G) insects (H) an area swollen with pus
A:
A