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: Katie is rubbing her hands on her leg. One hand rubs fast, the other hand rubs slow. The hand that will be warmer in the end is the one that moves 
 Option1: faster 
 Option2: slower 
 Explanation: Friction causes the molecules on rubbing surfaces to move faster, so they have more energy. This gives them a higher temperature, and they feel warmer.

A: faster
****
Q: Question: When you are mixing paints if you add less water the colors will be 
 Option1: darker 
 Option2: lighter 
 Explanation: If the kidneys remove less water from the blood, the blood will look darker, because there is less water in it.

A: darker
****
Q: Question: Quent reduces the energy of a liquid. He notices that the particles in the liquid 
 Option1: slow down 
 Option2: speed up 
 Explanation: As the liquid particles lose energy, their movement slows down even more. As their movements become slower and slower, the attractive forces between become stronger.

A:
slow down
****