Which equation represents the reaction whose ΔH, represents…

Which equation represents the reaction whose ΔH, represents the standard enthalpy of formation of CHCl3(l) at 25°C? (i.e., for which is ΔH = ΔH°f of CHCl3) A) CHCl3(l) → C(s) + H(g) + 3 Cl(g) B) C(s) + H(g) + 3 Cl(g) → CHCl3(l) C) C(s) + 1/2 H2(g) + 3/2 Cl2(g) → CHCl3(l) D) 2 C(s) + H2(g) + 3 Cl2(g) → 2 CHCl3(l)