The standard enthalpy of formation ($$\Delta_fH^\circ_{298}$$) for methane, CH$$_4$$ is $$-74.9$$ kJ mol$$^{-1}$$. In order to calculate the average energy given out in the formation of a C-H bond from this it is necessary to know which one of the following?

A

The dissociation energy of the hydrogen molecule, H$$_2$$.

B

The first four ionisation energies of carbon.

C

The dissociation energy of H$$_2$$ and enthalpy and sublimation of carbon (graphite).

D

The first four ionisation energies of carbon and electron affinity of hydrogen.