$2\,{\sin ^2}\beta + 4\,\,\cos \,(\alpha + \beta )\,\,\sin \,\alpha \,\sin \,\beta + \cos \,2\,(\alpha + \beta ) = $

  • [IIT 1977]
  • A

    $\sin \,\,2\alpha $

  • B

    $\cos \,\,2\beta $

  • C

    $\cos \,\,2\alpha $

  • D

    $\sin \,\,2\beta $

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