Urn $A$ contains $6$ red and $4$ black balls and urn $B$ contains $4$ red and $6$ black balls. One ball is drawn at random from urn $A$ and placed in urn $B$. Then one ball is drawn at random from urn $B$ and placed in urn $A$. If one ball is now drawn at random from urn $A$, the probability that it is found to be red, is

  • [IIT 1988]
  • A

    $\frac{{32}}{{55}}$

  • B

    $\frac{{21}}{{55}}$

  • C

    $\frac{{19}}{{55}}$

  • D

    None of these

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