A centrifugal compressor assembly consists of which of the following?

Correct Answer: Option D — A rotating impeller and a stationary diffuser.

A centrifugal compressor accelerates air radially outward using a rotating impeller, which imparts kinetic energy to the fluid. This high-velocity air then enters a stationary diffuser, where the flow area increases, converting the kinetic energy into static pressure before the air enters the combustion chamber.