Answer
$-4$
Work Step by Step
The general form of a matrix of order $ 2 \times 2$ is:
$det \ A=\begin{bmatrix} p & q \\ r & s\end{bmatrix}=ps-qr$
Since Column-1 has the most zeroes, we choose Column-1. It has sign array $(+,+)$ as we go down.
Now, $det \ A =0+0+(-1) \begin{bmatrix} 1 & -2 \\ 1 & 2 \end{bmatrix}=-1(2+2)=-4$
