Recall the definitions of the concentration terms

• Molality $(m)$: $m = \frac{\text{moles of solute}}{\text{mass of solvent in kg}}$
• Weight fraction of solute: $\text{weight fraction} = \frac{\text{mass of solute}}{\text{mass of solution}}$
• Molarity $(M)$: $M = \frac{\text{moles of solute}}{\text{volume of solution in litre}}$
• Mole fraction of solute: $x = \frac{\text{moles of a component}}{\text{total moles in solution}}$

Check which quantities depend on temperature

Temperature affects volume significantly due to thermal expansion, but it does not change the mass or number of moles of solute/solvent in an ordinary closed solution.

• Molality depends on moles of solute and mass of solvent. Neither changes with temperature. $\Rightarrow \text{Molality does not change}$

• Weight fraction depends on masses. Mass does not change with temperature. $\Rightarrow \text{Weight fraction does not change}$

• Molarity depends on volume of solution. Since volume changes with temperature, $\Rightarrow \text{Molarity changes with temperature}$

• Mole fraction depends on moles. Number of moles does not change with temperature. $\Rightarrow \text{Mole fraction does not change}$

Evaluate options

• A: molality — No
• B: weight fraction of solute — No
• C: molarity — Yes
• D: mole fraction — No

Final answer

The quantity that changes with increase of temperature is: $\boxed{\text{C: molarity}}$

Comparison with stored correct answer

Stored correct answer: C

My derived answer: C

Hence, they agree.