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: What happens to water when it absorbs salt? 
 Option1: lower density 
 Option2: Higher Density 
 Explanation: Water becomes more dense when it is colder and when it has more salt.

A: Higher Density
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Q: Question: If Mona is comparing sandpaper with notebook paper and she determines that sandpaper is rougher then notebook paper, which object has more friction? 
 Option1: sandpaper 
 Option2: notebook paper 
 Explanation: Rougher surfaces have more friction between them than smoother surfaces.

A: sandpaper
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Q: Question: If Milo decreases the concentration of hydrogen ions in his swimming pool, what happens to the acidity of his pool? 
 Option1: increases 
 Option2: decreases 
 Explanation: With a higher concentration of hydrogen ions, a solution is more acidic but has a lower pH.

A:
decreases
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