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: Flatworms belong to the phylum Platyhelminthes., Fact2: Most of the flatworms are parasitic, although the Turbellaria are free-living in fresh water., Question: Phylum Platyhelminthes are mostly what? (A) animals (B) engorged (C) fungi (D) infected (E) parasitic (F) insects (G) huge (H) free living
A:
E