All four scientists were very important in the development of cell theory. One scientist's research stands out in proving that disease is caused by microorganisms. Which scientists is this?

Louis Pasteur

Explanation:

Although louis was a great scientist who made contributions to the cell theory postulating that cells come from preexisting cells, he was a renowned and father of microbiology. He proved that diseases are caused by microorganisms, developed the first vaccine and provided logical ground knowledge on fermentation and brewing.