If $\cos \alpha+3 \cos 3 \beta+5 \cos 5 \gamma=0$,$\sin \alpha+3 \sin 3 \beta+5 \sin 5 \gamma=0$ and $\cos 3 \alpha+27 \cos 9 \beta+125 \cos 15 \gamma=\left(\lambda^2-4\right) \cos (\alpha+3 \beta+5 \gamma)$,then $\lambda$ is equal to

  • A
    $\pm 2 \sqrt{2}$
  • B
    $\pm 2 \sqrt{5}$
  • C
    $\pm 7$
  • D
    $\pm \sqrt{29}$

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