Q. A solution of urea (mol mass \(56 \mathrm{gmol}^{-1}\) ) boils at \(100.18^{\circ} \mathrm{C}\) at the atmospheric pressure. If \(K_{f}\) and \(K_{b}\) for water are \(1.86\) and \(0.512 \mathrm{Kkg} \mathrm{mol}^{-1}\) the above solution will freeze at
A \(-6.54^{\circ} \mathrm{C}\)
B \(6.54^{\circ} \mathrm{C}\)
C \(0.654^{\circ} \mathrm{C}\)
D \(-0.654^{\circ} \mathrm{C}\)