If matrix $A = \begin{bmatrix} 3 & 2 & 4 \\ 1 & 2 & -1 \\ 0 & 1 & 1 \end{bmatrix}$ and $A^{-1} = \frac{1}{K} \text{adj}(A)$,then $K$ is:

  • A
    $7$
  • B
    $-7$
  • C
    $\frac{1}{7}$
  • D
    $11$

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