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: Phytoplankton are bacteria and algae that use sunlight to make food., Fact2: Most copepods feed on phytoplankton., Question: what do most copepods feed on? (A) animals (B) bacteria and algae (C) density (D) body water (E) scarce resources (F) salt and water. (G) an organism's body (H) oxygen
A:
B