Let $b_1, b_2,......, b_n$ be a geometric sequence such that $b_1 + b_2 = 1$ and $\sum\limits_{k = 1}^\infty  {{b_k} = 2} $ Given that $b_2 < 0$ , then the value of $b_1$ is 

  • A

    $2 - \sqrt 2 $

  • B

    $1 + \sqrt 2 $

  • C

    $2 + \sqrt 2 $

  • D

    $4 + \sqrt 2 $

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