Pure Benzene freezes at $5.4 ^{\circ}\;C$. A solution of $0.223 \;g$ of phenyl acetic acid $(C_6 H_5 CH_2 COOH)$ in $4.4\;g$ benzene $(K_f =5.12 K\; Kg\;mol^{-1}) $ freezes at $4.47 ^{\circ}$ . From this observation , one can conclude that

Question

$\begin{array}{1 1} \text{phenyl acetic acid exists as such in benzene} \\ \text {phenyl acetic acid undergoes partial ionization in benzene} \\ \text {phenyl acetic acid undergoes complete ionization in benzene} \\ \text{phenyl acetic acid dimerizes in benzene} \end{array} $