Which of the following describes a property of water that helps sustain marine life forms? (5 points)
a. Open spaces in water's solid structure makes its solid state less dense than its liquid state.
b. Water contracts on cooling below 4 °C, lowering its density until it reaches 0 °C.
c. Water freezes from bottom to top, which allows it to form a solid layer of ice only at the bottom of rivers and lakes.
d. Water has a very low specific heat capacity, allowing it to heat up quickly.