Answer: B) The identity of the solvent
Explanation:
Basically, the solvent is the liquid in which a solute is dissolved in. But the solute is the material to be dissolved.
Now in this case, the solute in the first solution is glucose and the solute in the second solution is an unidentified covalent solid material.
This means that:
• the identity of the solute cannot be identical in each solutions, which also means that the freezing points and densities of the solutions cannot be identical too.
• the only thing that is sure to be identical in the solution is the identity of the solvent.