Which statement best describes an effect of the low density of frozen water in a lake?

A. When water freezes, it contracts, decreasing the water level in a lake.
B.Water in a lake freezes from the bottom up, killing most aquatic organisms.
C.When water in a lake freezes, it floats, providing insulation for organisms below.
D.Water moves thermal energy from the land around a lake, causing the lake to freeze.