The rate of the heterogeneous catalytic reaction A(g) + B(g) → C(g) is given by -rA = k.KA.pA.PB/(1 + KA.PA + Kc.pc), where KA and Kc are the adsorption equilibrium constants. The rate controlling step for this reaction is_______________?
A. Absorption of A
B. Surface reaction between absorbed A and absorbed B
C. Surface reaction between absorbed A and B in the gas phase
D. Surface reaction between A in the gas phase and absorbed B