The ability of water to absorb heat and thus buffer changes in temperature is important for

The right answer is temperature homeostasis.

The concept of homeostasis was mentioned for the first time in 1866 by French physician and physiologist Claude Bernard. Today, the concept has been extended to other systems than purely organic ones, and can also be applied to an ecosystem.

Homeostasis is the ability of a system to maintain the equilibrium of its internal environment, regardless of external constraints. At the level of an organism, it is the set of parameters that must remain constant or adapt to specific needs, such as body temperature, blood glucose, blood pressure or heart rate.

Water has a very high heat capacity of all fluids. Because of this ability, water bodies act as buffers or regulators against high temperature changes.

your answer should be c) enjoy!