Fact 1: Corals form large colonies in shallow tropical water.

Fact 2: Coral is the calcite shell of the coral animal.

Given the two facts above, answer the question "Animals with _ form large colonies in shallow tropical water" with the following options: 
- calcite shells
 - an organism's body
 - Absorb light
 - biological diversity
 - Leptospirosis
 - produce offspring
 - allow growth
 - to stay warm


 

 calcite shells        