In the root locus plot shown in the figure, the pole/zero marks and the arrows have been removed. Which one of the following transfer functions has this root locus?
- $\frac{s+1}{(s+2)(s+4)(s+7)} \\$
- $\frac{s+4}{(s+1)(s+2)(s+7)} \\$
- $\frac{s+7}{(s+1)(s+2)(s+4)} \\$
- $\frac{(s+1)(s+2)}{(s+7)(s+4)}$