You are presented with the question "What content increases melting points of solids?" and the following answer choices: 
- salt
 - Joules
 - water
 - fats
 - heat
 - glass
 - sugar
 - coal

Now knowing that adding salt to a solid decreases the freezing point of that solid and water density decreases with temperature and increases with salt content, choose the best answer.


 

 salt        