Find the system function for the LTI system represented by the following differential equation.

$y^{\text{'}\text{'}}(t)+2y^{\text{'}}(t)+y(t)=x^{\text{'}}(t)+x(t)$

Select one:

A$.,H(s)=\frac{s+1}{s^2+2s+1}$

B$.,H(s)=\frac{s^2+s}{s^2-2s-s}$

C$.H(s)=\frac{s^2+s}{s^2+2s+1}$

D$.H(s)=\frac{s}{s^2+2s+1}$