Fact 1: Some parasites live on the surface of their host.

Fact 2: Leeches are external parasites.

Given the two facts above, answer the question "Where do leeches live in relation to their hosts?" with the following options: 
- In their beds
 - body water
 - competing for resources
 - In their shoes
 - loose soil
 - In their intestines
 - important habitats
 - On their surface


 

        On their surface 