Which among the following is an example of soluble impurities?

In water, two kinds of impurities can be present. They are soluble impurities and insoluble impurities. Salt is an example of soluble impurities. A substance can be called soluble if it dissolves when it is added to water. When salt is added to water, it gets dissolved. Sand and germs are examples of insoluble impurities. Because when they are added to water, they don't get dissolved.