Final answer:
A 1.0 m NaNO3 solution would have the highest freezing point due to its greater concentration of particles.
Step-by-step explanation:
The freezing point of an aqueous solution depends on the concentration of particles in the solution. The greater the concentration of particles, the lower the freezing point.
Out of the given choices, a 1.0 m NaNO3 solution would have the highest freezing point. This is because NaNO3 dissociates into two ions (Na+ and NO3-) in water, resulting in a greater concentration of particles compared to the other options.