The sum of the series $\sum\limits_{r = 0}^n {{{( - 1)}^r}\,{\,^n}{C_r}\left( {\frac{1}{{{2^r}}} + \frac{{{3^r}}}{{{2^{2r}}}} + \frac{{{7^r}}}{{{2^{3r}}}} + \frac{{{{15}^r}}}{{{2^{4r}}}} + .....m\,{\rm{terms}}} \right)} $ is

  • A

    $\frac{{{2^{mn}} - 1}}{{{2^{mn}}({2^n} - 1)}}$

  • B

    $\frac{{{2^{mn}} - 1}}{{{2^n} - 1}}$

  • C

    $\frac{{{2^{mn}} + 1}}{{{2^n} + 1}}$

  • D

    None of these

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  • [AIEEE 2011]