Definition: 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: Biomass is the total mass of organisms at a trophic level., Fact2: Herbivores are the second trophic level and graze on plants., Question: Biomass is the total mass of organisms on a level such as what (A) Energy (B) trees (C) Energy. (D) bottom of feet (E) herbivores (F) kinetic energy (G) animals (H) energy usage
Output:
E