The freezing point (in$^{\large\circ}C)$ of a solution containing 0.1g of $K_3[Fe(CN)_6]$ (mol .wt .329) in 100g of water $(K_t=1.86Kkgmol^{-1})$

Question

$\begin{array}{1 1}(a)\;-5.7\times 10^{-2}\\(b)\;-5.7\times 10^{-3}\\(c)\;-1.2\times 10^{-2}\\(d)\;-2.3\times 10^{-2}\end{array}$