Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on the phenomenon of
- Atotal internal reflectionCorrect
- Binterference
- Cdiffraction
- Dpolarisation
Explanation
The correct answer is A because endoscopy relies on fiber optic cables to transmit light and images. These cables consist of thin glass or plastic fibers that use the principle of total internal reflection. When light enters the fiber at a specific angle, it reflects repeatedly off the inner walls without escaping, allowing the light to travel through curved paths deep into the body to illuminate and visualize internal organs. Other phenomena like interference, diffraction, and polarisation relate to the wave nature of light but are not the primary mechanisms used to guide light through endoscopes.

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