$\frac{1}{{1!(n - 1)\,!}} + \frac{1}{{3!(n - 3)!}} + \frac{1}{{5!(n - 5)!}} + .... = $

  • A

    $\frac{{{2^n}}}{{n!}}$; for all even values of $n$

  • B

    $\frac{{{2^{n - 1}}}}{{n!}}$; for all values of $n$ i.e., all even odd values

  • C

    $0$

  • D

    None of these

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