Filtration is an example of a process that can be used to separate , but not . A) water; gas B) mixtures; pure substances C) pure substances; mixtures D) homogeneous mixtures; heterogeneous mixtures

The correct answer is

B) mixtures; pure substances

Explanation:

Filtration is a process that can be applied to solids or other larger size particles suspended in a mixture containing one or particles of different sizes such as solids in liquids or gas such that the liquid is meant to pass through the tiny holes on the filtering medium or mesh. The liquid that passes through the filtering medium is known as the filtrate

As such filtration can only be used to separate  particles of  mixtures containing particles of different sizes but it cannot be used to separate particles of a pure substance which has particles of only one size

these nuts

dynamic equilibrium is the answer.