Answer:
A. Lakes
Explanation:
Usually the open ocean has too much movement and higher temperatures to freeze over, so that excludes salt marches and estuary as well. Mangrove forests usually survive in salt water areas, which again the salt and movement of salt water allows for the water to not freeze over. With lakes, they are usually smaller bodies of water found all over the world, and can easily have the top freeze over, since there's no salt, not as much movement, and temperatures can vary more often.
