C. Water expands on cooling below 4 °C, increasing in volume until it reaches 0 °C.
Explanation:
The volume occupied by ice is greater than the volume of water.
The maximum density of water is at 4°C.
The hydrogen bond in ice gives it an open cage like structure which makes it volume higher and density lower as compared to liquid water. As we increase the temperature the volume decreases due to breaking of these bonds so its density increases till 4°C. After this temperature the increase in volume due to change in state is more and thus its volume increases and density decreases.
