Two alternative syntheses of substance D from substance A are proposed.
Pathway I:
A → B ΔH = +40 kJ
B → D ΔH = −10 kJ
Pathway II:
A → C ΔH = +15 kJ
C → D ΔH = +5 kJ
Which pathway requires less net energy input to produce one mole of D from A? Support your answer with a brief calculation.