If $5{\cos ^2}\theta + 7{\sin ^2}\theta - 6 = 0$, then the general value of $\theta $ is

  • A

    $2n\pi \pm \frac{\pi }{4}$

  • B

    $n\pi \pm \frac{\pi }{4}$

  • C

    $n\pi + {( - 1)^n}\frac{\pi }{4}$

  • D

    None of these

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