What instrument is used to test hearing?

The tuning fork is specifically designed for testing hearing as it produces a pure musical note that can help assess a person's auditory function. When struck, it vibrates and generates sound waves that can be heard, allowing for a straightforward evaluation of the hearing ability in an individual. It is commonly used in clinical settings to perform tests like the Rinne and Weber tests, which help differentiate between conductive and sensorineural hearing loss.

The other instruments listed do not serve this primary function. A stethoscope is mainly used to listen to internal body sounds, such as heartbeats and lung sounds. A sphygmomanometer measures blood pressure, and a thermometer is used to assess body temperature. Unlike the tuning fork, these instruments are tailored for entirely different aspects of medical examinations.