The condition of the curves $a{x^2} + b{y^2} = 1$and $a'{x^2} + b'{y^2} = 1$ to intersect each other orthogonally, is

  • A

    $\frac{1}{a} - \frac{1}{{a'}} = \frac{1}{b} - \frac{1}{{b'}}$

  • B

    $\frac{1}{a} + \frac{1}{{a'}} = \frac{1}{b} + \frac{1}{{b'}}$

  • C

    $\frac{1}{a} + \frac{1}{b} = \frac{1}{{a'}} + \frac{1}{{b'}}$

  • D

    None of these

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