Help, TT 10-4

If S is the sum of the reciprocals of the consecutive integers from 91 to 100, inclusive, which of the following is less than S?

I. 1/8

II. 1/9

III. 1/10 

A.
                    None

B.  I only

C.
                    III only

D.
                    II and III only

E.  I, II, and III

S ＝1/91+ 1/92+...+1/100

S > 1/100+ 1/100 + ...+1/100 = 10*(1/100)=1/10

S < 1/90 + 1/90 + ...+ 1/90 = 10*(1/90) = 1/9

1/10 < S < 1/9

III only