Question

If n is a positive integer, then lim (n-->infinity) (1/n) [1/(1+(1/n)) + 1/(1+(2/n))+...+1/(1+(n/n)] is?
the above can be expressed as
a.) integral from 0 to 1 of (1/x) dx
b.) integral from 1 to 2 of (1/(x+1))dx
c.) integral from 1 to 2 of (x)dx
d.) integral from 1 to 2 of (2/(x+1))
e.) integral from 1 to 2 of (1/x)

please show me how u got the answer thanks a lot!