If $f(x)$ is a quadratic expression such that $f(1) + f (2)\, = 0$ , and $-1$ is a root of $f(x)\, = 0$, then the other root of $f(x)\, = 0$ is

  • [JEE MAIN 2018]
  • A

    $ - \frac{5}{8}$

  • B

    $ - \frac{8}{5}$

  • C

    $  \frac{5}{8}$

  • D

    $ \frac{8}{5}$

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