Separating salt and water mixture is possible because what is correct?

Correct answer: They are a physical mixture

The direct answer is C: salt and water form a physical mixture. In a mixture, substances are combined physically rather than forming one new substance in a fixed chemical ratio. Salt water can be separated because water and dissolved salt retain separable properties. Step by step, evaporation removes water as vapour and leaves salt behind; distillation boils and condenses water so that water is collected separately while salt remains in the flask. Option A is wrong because saying they are chemically combined would suggest formation of a compound with a fixed composition, which is not the normal description of salt water. Option B is wrong because whether substances are elements does not explain the separation; salt itself is a compound and water is also a compound, yet they can make a mixture. Option C is correct because physical mixtures can usually be separated by physical methods. Option D is meaningless and wrong because both salt and water are matter. Memory cue: if components can be separated by filtration, evaporation, distillation, or another physical method, suspect a mixture.