Which instrument is used to listen to internal body sounds?

The stethoscope is the instrument specifically designed for listening to internal body sounds, such as the heart beating, lungs breathing, and bowels functioning. It amplifies these sounds, allowing healthcare providers to assess the condition of internal organs and help diagnose various medical conditions. This tool is essential in clinical settings for conducting physical examinations, as it provides vital information about a patient's health.

Thermometers measure body temperature, which is unrelated to listening to internal sounds. Sphygmomanometers are used to measure blood pressure, focusing on the circulatory system rather than providing acoustic information. Otoscopes are designed for examining the ears, specifically to view the ear canal and eardrum, not for listening to the sounds produced by internal organs. Each of these instruments serves distinct purposes in a medical context, making the stethoscope the correct choice for listening to internal body sounds.