You are presented with the question "Where do coral colonies form?" and the following answer choices: 
- ocean loor
 - south atlantic
 - warm, clear, shallow waters
 - exposure to the sun
 - arctic ocean
 - To conserve energy
 - sub-units of species
 - To another location like underground

Now knowing that corals form large colonies in shallow tropical water and coral reefs are found in the warm, clear, shallow waters of tropical oceans worldwide, choose the best answer.


 

   warm, clear, shallow waters      