if `a,a_1,a_2,a_3,.........,a_(2n),b` are in `A.P.` and `a,g_1,g_2,............g_(2n) ,b` are in `G.P.` and `h` is `H.M.` of `a,b` then `(a_1+a_(2n))/(g_1*g_(2n))+(a_2+a_(2n-1))/(g_2*g_(2n-1))+............+(a_n+a_(n+1))/(g_n*g_(n+1))` is equal
A. `(2n)/(h)`
B. 2nh
C. nh
D. `(n)/(h)`
