In a meeting,$70 \%$ of the members favour and $30 \%$ oppose a certain proposal. $A$ member is selected at random. We take $X=0$ if he opposes the proposal and $X=1$ if the member is in favour. Then the variance of $X$ is:

  • A
    $0.21$
  • B
    $0.23$
  • C
    $0.25$
  • D
    $0.27$

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