Let ${\left( {1 + x + {x^2}} \right)^{20}}\left( {2x + 1} \right) = {a_0} + {a_1}{x^1} + {a_2}{x^2} + ... + {a_{41}}{x^{41}}$ , then $\frac{{{a_0}}}{1} + \frac{{{a_1}}}{2} + .... + \frac{{{a_{41}}}}{{42}}$ is equal to 

  • A

    $\left( {\frac{{{2^{21}} - 1}}{{21}}} \right)$

  • B

    $\left( {\frac{{{3^{21}} - 1}}{{21}}} \right)$

  • C

    $\left( {\frac{{{2^{20}} - 1}}{{20}}} \right)$

  • D

    $\left( {\frac{{{3^{20}} - 1}}{{20}}} \right)$

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