Concept:Effective rate = (1+nr)n−1, where r is nominal rate and n is compounding frequency per year.Explanation:Nominal rate r=9.9%=0.099, compounded monthly (n=12).Monthly factor: 1+120.099=1+0.00825=1.00825=40004033.Given (40004033)12=1.1036.Thus effective rate = 1.1036−1=0.1036=10.36%.Answer:10.36% which corresponds to option A.