Fact 1: Polyps usually reproduce asexually.

Fact 2: Reefs are built by tiny organisms called polyps.

Given the two facts above, answer the question "What are built by organisms that usually reproduce asexually?" with the following options: 
- legumes
 - reefs
 - Roads
 - dams
 - bridges
 - bushes
 - bacteria
 - trees


 

  reefs       