For which matrix would Cramer's rule NOT apply to solve the system Ax=bAx = bAx=b?
A=(2132)A = \begin{pmatrix} 2 & 1 \\ 3 & 2 \end{pmatrix}A=(2312)
A=(1224)A = \begin{pmatrix} 1 & 2 \\ 2 & 4 \end{pmatrix}A=(1224)
A=(3−112)A = \begin{pmatrix} 3 & -1 \\ 1 & 2 \end{pmatrix}A=(31−12)
A=(−2311)A = \begin{pmatrix} -2 & 3 \\ 1 & 1 \end{pmatrix}A=(−2131)