Magnesium Chloride Is Often Used to Melt Ice on Sidewalks $\degree$

Magnesium chloride is often used to melt ice on sidewalks.Considering that the solubility of magnesium chloride 95.21 (g/mol) in water is 54.3 g per 100.0 g of water, what is the lowest temperature that you would expect to be able to melt ice with magnesium chloride? Assume ideal behavior.(K_f (water) =1.86 $\degree$ C/m)

A) (-41.0 $\degree$ C)
B) (-31.8 $\degree$ C)
C) (-10.6 $\degree$ C)
D) (-25.0 $\degree$ C)
E) (-29.2 $\degree$ C)