NaCl solution likely has the highest boiling point among the options listed due to the ionic nature of NaCl and its impact on increasing the boiling point significantly.
The boiling points of urea solution and sucrose solution would be higher than that of pure water but lower than that of the NaCl solution.
The boiling point of solution (4) would depend on the nature and concentration of the solute, so without more information, it's challenging to determine its boiling point relative to the others.