已知：①2C(s)+O₂(g)="===2CO(g) " ΔH=－221.0 kJ·mol^-1;
②2H₂(g)+O₂(g) ====2H₂O(g) ΔH=－483.6 kJ·mol^-1。则制备水煤气的反应C(s)+H₂O(g) ====CO(g)+H₂(g)的ΔH为

A．+262.6 kJ·mol^-1

B．－131.3 kJ·mol^-1

C．－352.3 kJ·mol^-1

D．+131.3 kJ·mol^-1