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The concentration of solutions are generally expressed in terms of molarity, molality, normality, and weight percent. The formation of the solutions itself has many ramifications. The solubility of solutes differ considerably from one other. Some of the factors that can influence the solubility include temperature and pressure. Solubility depends on other factors as well. Given below in Figure-1 is a graph which depicts solubility differences of some solutes.

Quite often, the freezing and boiling point changes that are brought about by the dissolved solutes can be predicted reasonably. But this is not always the case.

The predictions and calculations are done for freezing point depression (DT_{f}) based on the following formula:

DT_{f} = K_{f} m,

where m is the molality and K_{f} is the freezing point depression constant. (K_{f}= 1.86 ^{o}C/*m*)

For boiling point elevation (DT_{b}), the calculations are based on the following formula:

DT_{b} = K_{b} m,

where m is the molality and K_{b} is the boiling point elevation constant. (K_{b} = 0.512 ^{o}C/*m*)

The graph in the passage shows the solubilities of some compounds (salts). Which of the following is most likely true regarding the Compounds A, B, C and D?