An aqueous drug solution had an observed first order rate (kobs) constant of 0.058 h^-1at pH of 2.0 and 0.0025 h^-1 at a pH of 6.5. The solvent catalysis rate constant(ko) will be:

A. 3.29x10^-3 h^-1

B.4.87x10^-3 h^-1

C.7.35x10^-3 h^-1

D.2.50x10^-3 h^-1

E. 1.45x10^-3 h^-1