Which of the following solution in water will have the highest freezing point?
Option 1 Solution which is 0.1 M in KNO3 and 0.2 M in Ba(NO3)2. Option 2 Solution which is 0.1 M in Ca(NO3)2 and 0.1 M Ba(NO3)2. Option 3 Solution which is 0.2 M in urea and 0.2 M glucose. Option 4 Solution which is 0.1 M both in Al2(SO4)3 and 0.1 M K2SO4. A: Al2O3
B: Cr2O3
C: V2O5
D: MnO2