Because the intention is to boil the solution, the purpose of the solvent is to dissolve so it has a higher boiling point so ensure it stays in liquid form and doesn't evaporate into a gas
also, a pure solvent is made of 1 substance so it has 1 boiling point and the solution must evaporate/boil first
I believe it is D. Hope this helps you!
A, B and D should be the ones you should check