If the length of the tangents drawn from the point $(1,2)$ to the circles ${x^2} + {y^2} + x + y - 4 = 0$ and $3{x^2} + 3{y^2} - x - y + k = 0$ be in the ratio $4 : 3$, then $k =$

  • A

    $7/2$

  • B

    $21/2$

  • C

    $-21/ 4$

  • D

    $7/4$

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