In the depression of freezing point experiment, it is found that
a) The vapor pressure of the solution is less than that of pure solvent
b) The vapor pressure of the solution is more than that of pure solvent
c) Only solute molecules solidify at the freezing point
d) Only solvent molecules solidify at the freezing point

The vapour pressure of a solution is less than that of a pure solvent, according to the depression in freezing point experiment. At the freezing point, only solvent molecules solidify.
The temperature at which the liquid's vapour pressure equals the solid's vapour pressure is graphically the temperature at which the liquid's vapour pressure curve intersects the solid's. The freezing point of a non-volatile solute decreases when it is dissolved in a liquid.

Therefore Option C is the correct answer