You are presented with the question "Where do corals form large colonies?" and the following answer choices: 
- Mars
 - new World
 - Sediment
 - shoreline
 - environment
 - Absorb light
 - loose soil
 - polyps

Now knowing that corals form large colonies in shallow tropical water and water is shallow at the shore with gradual deepening, choose the best answer.


 

    shoreline     