Answer:
O Hooke and Leeuwenhoek
Step-by-step explanation:
The scientists, O Hooke and Leeuwenhoek were prominent scientists. In fact, they are credited with being the pioneers of science especially the field of microorganisms. To be more specific, the two great scientists discovered what are known as protozoa. This was done specifically by Van Leeuwenhoek who discovered the single celled protozoa ,which were termed animalcules. In addition, the most prominent feature of the research and discovery was Leeuwenhoek's use of a self-designed microscope.