Which one of the following is an example of the First Law of Thermodynamics?

A) As time passes, your room becomes
messier unless you spend energy to clean it.

B) Water will only become ice if it is in a very
cold environment.

C) When a combustion reaction produces
heat, that heat is absorbed by the air around
the reaction

D) A chemical ice pack feels cold because it is
reducing the energy of the universe.