If $\frac{1}{{p + q}},\;\frac{1}{{r + p}},\;\frac{1}{{q + r}}$ are in $A.P.$, then

  • A

    $p,\;,q,\;r$ are in $A.P.$

  • B

    ${p^2},\;{q^2},\;{r^2}$ are in $A.P.$

  • C

    $\frac{1}{p},\;\frac{1}{q},\;\frac{1}{r}$ are in $A.P.$

  • D

    None of these

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