Which of the following materials could be used as a radiographic film?

Radiographic film is designed to capture images produced by radiation in a manner that allows for clear visualization of internal features in a material being tested. Silver halide is the correct answer because it is the primary light-sensitive compound used in traditional radiographic films. When exposed to radiation, silver halide crystals undergo a chemical change, allowing for the formation of an image after the film is developed.

This chemical sensitivity is crucial for the radiographic process, as it ensures that the film can accurately record the patterns formed by the radiation passing through the object being inspected. Unlike aluminum or plastic, which do not have the necessary properties for image formation, silver halide effectively responds to ionizing radiation in a way that can be captured and later visualized as an image.

Glass, while it does have some imaging applications, is not conducive to the traditional radiographic film process primarily because it does not possess the light-sensitive characteristics required for producing the same types of images seen with silver halide films. Therefore, silver halide stands out as the appropriate material for radiographic film in non-destructive testing contexts.