Q: 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: Some parasites live on the surface of their host., Fact2: Leeches are external parasites., Question: Where do leeches live in relation to their hosts? (A) In their beds (B) body water (C) competing for resources (D) In their shoes (E) loose soil (F) In their intestines (G) important habitats (H) On their surface
A:
H