Right choice is (b) Molarity will change but not Molality
The explanation: Molarity is the number of moles of solute per kilogram of the Solvent. That is because molarity does not depend on temperature, (neither on number of moles of solute nor mass of solvent will be affected by changes of temperature). While molarity changes as temperature changes because molarity is affected by temperature. This is because it is based on the volume of the solution, and the volume of a substance will be affected by changes in temperature.