Simplify 1a+1ba+b\frac{\frac{1}{a} + \frac{1}{b}}{a+b}a+ba1+b1.
1ab\frac{1}{ab}ab1
a+bab\frac{a+b}{ab}aba+b
1a+b\frac{1}{a+b}a+b1
ababab