You Wish to De-Ice Your Driveway, So You Consider Buying

You wish to de-ice your driveway, so you consider buying 10 lb of NaCl, 10 lb of CaCl₂, or 10 lb of MgCl₂.Which of these would de-ice your driveway most effectively? Assume that ideal dissociation of the salts occurs and that colligative properties are the only consideration.

A) 10 lb of NaCl will de-ice best.
B) 10 lb of CaCl₂ will de-ice best.
C) 10 lb of MgCl₂ will de-ice best.
D) The three driveways will de-ice to the same extent.
E) 10 lb of CaCl₂ or 10 lb of MgCl₂ will de-ice equally well.