Given the task definition and input, reply with output. 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").

Fact1: Flatworms belong to the phylum Platyhelminthes., Fact2: Flatworms Flatworms or Platyhelminthes include flukes, tapeworms, and turbellarians., Question: flukes, tapeworms, and turbell are (A) major threat to health (B) types of flat leeches (C) Plant growth is reduced (D) types of earthworms (E) competing for resources (F) types of snakes (G) types of flatworms (H) parasites
G