If $z = \begin{bmatrix} 1 & 1+2i & -5i \\ 1-2i & -3 & 5+3i \\ 5i & 5-3i & 7 \end{bmatrix}$, then which of the following is true? (where $i = \sqrt{-1}$)

  • A
    $z$ is purely real
  • B
    $z$ is purely imaginary
  • C
    $z + \bar{z} = 0$
  • D
    $(z - \bar{z})i$ is purely imaginary

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