If the coefficient of $x ^7$ in $\left(a x-\frac{1}{b x^2}\right)^{13}$ and the coefficient of $x^{-5}$ in $\left(a x+\frac{1}{b x^2}\right)^{13}$ are equal, then $a^4 b^4$ is equal to :

  • [JEE MAIN 2023]
  • A

    $44$

  • B

    $22$

  • C

    $11$

  • D

    $33$

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