Answer:
B. He was the first to observe live cells in a sample of pond water.
Step-by-step explanation:
He was a self taught man that created the first microscopes which allowed him and others to see tiny organisms.
The other answers are not correct as Hans made the first microscope, cells existing in liquids were not a critical part of micro biology, and it was Schlieden and Schwann who created the cell theory that stated that all living things were made of cells.