Find the transfer function $\dfrac{Y(s)}{X(s)}$ of the system given below
- $\dfrac{G_{1}}{1-HG_{1}} + \dfrac{G_{2}}{1-HG_{2}} \\$
- $\dfrac{G_{1}}{1+HG_{1}} + \dfrac{G_{2}}{1+HG_{2}} \\$
- $\dfrac{G_{1}+G_{2}}{1+H (G_{1}+G_{2})} \\$
- $\dfrac{G_{1}+G_{2}}{1-H (G_{1}+G_{2})}$