Which of the following is the best definition of Hess' Law?

AHeat evolved in a given process can be expressed as the sum of the heats of several processes that, when added, yield the process of interest.

BThe enthalpy of a process is the difference between the enthalpy of the products and the enthalpy of the reactants.

CSince enthalpy is a state function, it will be different if a reaction takes place in one step or a series of steps.

DAt constant pressure the enthalpy change of a reaction is equal to the heat change of a reaction.

EHeat is always released by the decomposition of 1 mole of a compound into its constitute elements.