Answer:
THE DIAPHRAGM
Step-by-step explanation:
The diaphragm is present beneath the stage and above the condenser in a microscope. It is that rotating disk that can be seen just underneath the stage. The function of the diaphragm is to control the amount of light once the specimen or slide is placed on the microscope.
The diaphragm consists of holes of different sizes. These holes majorly function in varying the amount and intensity of light on the slide or specimen.