What was Rudolf Virchow's contribution to the cell theory?

He concluded that all cells come from preexisting cells.

He concluded that cells are the basic units of structure and function of all living things.

He concluded that all organisms are composed of cells.

He concluded that all cells are similar in composition and metabolic activities.

Virchow is credited with several very important discoveries. His most widely known scientific contribution is his cell theory, which built on the work of Theodor Schwann. He was one of the first to accept the work of Robert Remak, who showed the origins of cells was the division of pre-existing cells.

Explanation:

This is from my biology cells test here you go

The answer is A on edge