If the sum of an infinite $GP$ $a, ar, ar^{2}, a r^{3}, \ldots$ is $15$ and the sum of the squares of its each term is $150 ,$ then the sum of $\mathrm{ar}^{2}, \mathrm{ar}^{4}, \mathrm{ar}^{6}, \ldots$ is :

  • [JEE MAIN 2021]
  • A

    $\frac{5}{2}$

  • B

    $\frac{1}{2}$

  • C

    $\frac{25}{2}$

  • D

    $\frac{9}{2}$

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