What type of radiation can be detected by photographic film and fluorescent substances?

The correct answer is ultraviolet radiation. Photographic film and fluorescent substances are sensitive to ultraviolet light, which falls just beyond the visible spectrum. Photographic film contains light-sensitive chemicals that can capture the image formed by UV light exposure, leading to a visible photograph after development. Similarly, fluorescent materials can absorb ultraviolet light and then re-emit it as visible light, which is why they often appear to glow when exposed to UV radiation.

While infrared radiation is not detectable by photographic film, and both X-rays and gamma rays typically require specialized detectors due to their higher energy and penetrating nature, ultraviolet light is effectively captured by the methods mentioned in the question.