If $x, y, z$ are different from zero and $\left|\begin{array}{ccc}1+x & 1 & 1 \\ 1 & 1+y & 1 \\ 1 & 1 & 1+z\end{array}\right|=0$, then the value $x^{-1}+y^{-1}+z^{-1}$ is
(a) $x y z$
(b) $x^{-1} y^{-1} z^{-1}$
(c) $-x-y-z$
(d) $-1$
$\left|\begin{array}{ccc}1+x & 1 & 1 \\ 1 & 1+y & 1 \\ 1 & 1 & 1+z\end{array}\right|=0$
$\Rightarrow\left|\begin{array}{ccc}x & 0 & -z \\ 0 & y & -z \\ 1 & 1 & 1+z\end{array}\right|=0$ [Applying $R_{2} \rightarrow R_{2}-R_{3}$ and $\left.R_{1} \rightarrow R_{1}-R_{3}\right]$
$\Rightarrow x[y(1+z)+z]+1(y z)=0 \quad$ [Expanding along first column]
$\Rightarrow x[y+y z+z]+y z=0$
$\Rightarrow x y+x y z+x z+y z=0$
$\Rightarrow x y+y z+z x=-x y z$
$\Rightarrow \frac{x y}{x y z}+\frac{y z}{x y z}+\frac{z x}{x y z}=-\frac{x y z}{x y z}$
$\Rightarrow \frac{1}{z}+\frac{1}{x}+\frac{1}{y}=-1$
$\Rightarrow x^{-1}+y^{-1}+z^{-1}=-1$
Hence, the correct option is (d).