You are given a question or fill-in-the-blank question, two answer options (Option1 and Option2) and an Explanation. Your task is to find the correct answer (return the string of the correct option, not option1/2) for the given question from the given options and using explanation.

Q: Question: If Milo wants to make his water saltier and begins adding salt to the glass, what happens to the density of the glass of water? 
 Option1: decreases 
 Option2: increases 
 Explanation: If salt is added to a volume of water, there are more molecules in the same volume, so the water is denser.

A: increases
****
Q: Question: If someone has a larger than average physical heart then it will beat _____ in order to pump blood. 
 Option1: more 
 Option2: less 
 Explanation: When the heart expels more blood with each stroke, the heart has to beat less often in order to maintain the same volume of blood flow.

A: less
****
Q: Question: Will decreases the population of his model of the world's population. The amount of water scarcity, if no other variables are changed, will likely go 
 Option1: up 
 Option2: down 
 Explanation: Many of the worlds people live with water scarcity, and that percentage will increase as populations increase and climate changes.

A:
down
****