I think the answer is a cell..
The surface layer of the water freezes solid creating a barrier that insulates the ice below so that it keeps a steady temperature usually a few degrees above freezing (32 degrees).
A. Separated twins develo traits that differ according to the environments in which they are raised
C) Help with plant defense.
Many species are known to eat many plants, including flowers. To avoid being eaten, thorns in a rose bush help defend itself.
The answer is a hope it helps
