Aquatic organisms in lakes and ponds are often able to survive the water underneath a layer of ice because the water underneath the ice remains liquid. Which property of water is primarily responsible for creating these favorable conditions for aquatic life?

The property is that water expands when it freezes and oxygen is trapped inside

Explanation:

Underneath the frozen upper layer, the water remains in its liquid form and does not freeze. Also, oxygen is trapped beneath the layer of ice. As a result, fish and other aquatic animals find it possible to live comfortably in the frozen lakes and ponds. The oxygen is present in water under the ice and this oxygen is used for breathing by the marine and aquatic animals.