A second$-$order recursive system is described by the following difference equation $y[n]+5y[n-1]+4y[n-2]=x[n]$ where $y[-1]=2$ and $y[-2]=1$

Find the system response $($total solution$)$ for $x[n]=4u[n]$

Select one:

a$.,C_1(4{)}^n+C_2(-1{)}^n$

b$.C_1(-4{)}^n+C_2(-1{)}^n+0\mathrm{.}4u[n]$

c$.C_1(-4{)}^n+C_2(-1{)}^n+4u[n]$

d$.C_1(4{)}^n+C_2(1{)}^n+0\mathrm{.}4u[n]$