Which type of telescope uses one lens and two mirrors?

The correct answer, which identifies the type of telescope that uses one lens and two mirrors, is a catadioptric telescope. This design combines both lenses and mirrors in its optical system. Specifically, it typically features a primary mirror, a secondary mirror, and a lens, all working together to gather and focus light.

While a reflecting telescope uses mirrors exclusively, and a refracting telescope utilizes lenses without mirrors, the catadioptric system's hybrid approach allows for certain advantages, such as reduced optical aberrations and compact design. Cassegrain telescopes, which fall under the catadioptric category, also employ one lens and two mirrors, typically designed for longer focal lengths in a shorter physical space.

Understanding the components and configurations of these telescopes helps clarify why the catadioptric design is unique among optical instruments.