The overall closed loop transfer function \(\frac{{C\left( s \right)}}{{R\left( s \right)}},\) represented in the figure, will be

• A. \(\frac{{\{ {G_1}\left( s \right) + {G_2}\left( s \right)\} {G_3}\left( s \right)}}{{1 + \left( {{G_1}\left( s \right) + {G_2}\left( s \right)} \right)\left( {{H_1}\left( s \right) + {G_3}\left( s \right)} \right)}}\)
• B. \(\frac{{\left( {{G_1}\left( s \right) + {G_3}\left( s \right)} \right)}}{{1 + {G_1}\left( s \right){H_1}\left( s \right) + {G_2}\left( s \right){G_3}\left( s \right)}}\)
• C. \(\frac{{\left( {{G_1}\left( s \right) - {G_2}\left( s \right)} \right){H_1}\left( s \right)}}{{1 + \left( {{G_1}\left( s \right) + {G_3}\left( s \right)} \right)\left( {{H_1}\left( s \right) + {G_1}\left( s \right)} \right)}}\)
• D. \(\frac{{{G_1}\left( s \right){G_2}\left( s \right){H_1}\left( s \right)}}{{1 + {G_1}\left( s \right){H_1}\left( s \right) + {G_1}\left( s \right){G_3}\left( s \right)}}\)