The microscope helped Antoine van Leeuwenhoek discover "little animalcules" which were really the first descriptions of microscopic items such as: a. Bacteria b. All of the above c. Red Blood Cells d. Protozoa and Algae
The answer is bacteria. Red blood cells, Protozoa, and algae were discovered at a later time in history. He called bacteria "animalcules" because they moved and reproduced under the microscope (sort of like little animals).
