A scientist observes that lake water forced through a certain filter removes most of the particles in it. What is the process being used and what interpretation can the scientist make?

1. The process of filtration is working to remove residue from the lake water.

2. The process of filtration is working to remove all of the dissolved impurities from the water.

3. The process of evaporation has removed most of the particles, so the filter is unneeded.

4. The process of water force is keeping the water completely pure, so the filter is working.