Hi, I noticed no ones helped you yet so I'll try to. We can remove the third option because if the water evaporates then there will be no mass (Obviously.) It becomes a gas and I don't think gas has a great mass. (It rhymes too.) The last option seems logically correct for me. If you freeze water, it will continue to weigh the same. Same with boiling water; the mass stays the same. I would go with "Adding more water will increase the mass". Hope I helped you! Good Luck!