If $C_{x} \equiv^{25} C_{x}$ and $\mathrm{C}_{0}+5 \cdot \mathrm{C}_{1}+9 \cdot \mathrm{C}_{2}+\ldots .+(101) \cdot \mathrm{C}_{25}=2^{25} \cdot \mathrm{k}$ then $\mathrm{k}$ is equal to

  • [JEE MAIN 2020]
  • A

    $42$

  • B

    $45$

  • C

    $51$

  • D

    $48$

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  • [JEE MAIN 2021]