You are presented with the question "What increases in concentration when water evaporates?" and the following answer choices: 
- nektar
 - sugar
 - sweat
 - salt
 - potash
 - Gases
 - maples
 - energy

Now knowing that heating salt water causes the water to evaporate while the salt remains and when water evaporates, salts in the water remain and become more concentrated, choose the best answer.


 

    salt     