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Which one of the following transfer functions, upon a unit step change in disturbance at $t=0$, will show a stable time domain response with a negative initial slope (i.e., slope at $t=0$):

- $G\left ( s \right )=\frac{1}{s+1}-\frac{2}{s+4}$
- $G\left ( s \right )=\frac{1}{s+1}+\frac{2}{s+4}$
- $G\left ( s \right )=\frac{1}{s+1}+\frac{2}{s-4}$
- $G\left ( s \right )=\frac{1}{s-1}+\frac{2}{s-4}$