A certain linear time invariant system has the state and the output equations given below
\[
\begin{array}{c}
{\left[\begin{array}{l}
\dot{\mathrm{X}}_{1} \\
\dot{\mathrm{X}}_{2}
\end{array}\right]=\left[\begin{array}{rr}
1 & -1 \\
0 & 1
\end{array}\right]\left[\begin{array}{l}
\mathrm{X}_{1} \\
\mathrm{X}_{2}
\end{array}\right]+\left[\begin{array}{l}
0 \\
1
\end{array}\right] u} \\
y=\left[\begin{array}{ll}
1 & 1
\end{array}\right]\left[\begin{array}{l}
\mathrm{X}_{1} \\
\mathrm{X}_{2}
\end{array}\right]
\end{array}\]
If $X_{1}(0)=1, X_{2}(0)=-1, u(0)=0$, then $\left.\frac{d y}{d t}\right|_{t=0}$ is
- $1$
- $-1$
- $0$
- None of the above