If p+q+r=a+b+c=0, then the determinant vmatrix pa&qb&rc &ra&pb &pc&qa vmatrix equals

NDA 2017 Mathematics question

If , then the determinant \begin{vmatrix}pa&qb&rc\\qc&ra&pb\\rb&pc&qa\end{vmatrix} equals

Answer: (A)

Expanding: pa(qra^2-p^2bc)-qb(q^2ac-prb^2)+rc(pqc^2-r^2ab) = pqr(a^3+b^3+c^3)-abc(p^3+q^3+r^3). Since

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Question ID VK-028791