When 100 g each of the salts NaCl, $$\text{MgSO}_4$$, $$\text{Ca(NO}_3)_2$$ and $$\text{K}_2\text{CO}_3$$ were dissolved separately in 1.0 kg of water, the solution with the highest boiling point will be of

A

$$\text{Ca(NO}_3)_2$$

B

$$\text{MgSO}_4$$

C

NaCl

D

$$\text{K}_2\text{CO}_3$$