Final answer:
The medium of the laser is located in the resonating chamber, which plays a crucial role in the amplification of light through the stimulated emission of radiation.
Step-by-step explanation:
The medium of the laser, which is responsible for the amplification of light through a process known as stimulated emission of radiation, is contained in the C. resonating chamber. The resonating chamber is a key part of a laser's construction, where the lasing material is placed. When energy is pumped into the lasing material, it creates a population inversion setting the stage for stimulated emission to occur.
Photons repeatedly pass through the material, which is facilitated by mirrors on both ends of the chamber; one of these mirrors is partially silvered to let some light out as the usable laser beam. The process of optical pumping energizes the lasing material, and the use of totally silvered and partially silvered mirrors ensures that the light is amplified effectively.