For which of the following reactions does Kp = Kc?
A) H2(g) + I2(s) <-- --> 2HI(g)
B) 3Fe(s) + 4H2O(g) <-- --> Fe3O4(s) + 4H2(g)
C) 2SO2(g) + O2(g) <-- --> 2SO3(g)
D) C(s) + H2O(g) <--- --> CO(g) + H2(g)