Answer:
The correct answer is- cells
Step-by-step explanation:
While working with the cork through his homemade microscope he viewed some small compartments having empty spaces surrounded by walls which he called cells. Therefore Robert hook is credited to discover the unit of life that is cell.
Later scientists like Matthias Schleiden and Theodor Schwann gave the cell theory. Cell theory says that each organism is made up of cells and the cell is the smallest unit from which life is made up of and new cells can come from old cells only. So it was Robert Hooke who discovered small compartments which he called cells.