The answer is B
Cell were in existence long before the microscope was invented but could not be studied well. The invention of the microscope opened a whole new dimension of science . By using microscopes scientists have been able to discover the existence of microorganisms and study the structure of cells in astounding detail.
Since their invention ,microscopes have moved from simple, visible light refracting lenses to those which now use electrons such as the electron microscope which can magnify a cell up to 2 million times its size. An example of such a microscope is the JEM-ARM200F microscope in the university of Texas , San Antonio.
