$\sum\limits_{n = 1}^n {{1 \over {{{\log }_{{2^n}}}(a)}}} = $

  • A

    ${{n(n + 1)} \over 2}{\log _a}2$

  • B

    ${{n(n + 1)} \over 2}{\log _2}a$

  • C

    ${{{{(n + 1)}^2}{n^2}} \over 4}{\log _2}a$

  • D

    None of these

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