If the sum of the first $n$ terms of the series $\sqrt 3  + \sqrt {75}  + \sqrt {243}  + \sqrt {507}  + ......$ is $435\sqrt 3 $ , then $n$ equals

  • [JEE MAIN 2017]
  • A

    $18$

  • B

    $15$

  • C

    $13$

  • D

    $29$

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