What might result in a clear film after processing?

A clear film after processing often indicates that the film has not undergone proper development, which is why the option regarding no exposure or the use of fixer before developer is the correct choice.

When film is not exposed to x-rays, it remains clear because there are no latent images created on the film. Similarly, if fixer is applied before developer, it can also result in a clear film because the fixer halts the development process early, preventing any images from forming. The lack of exposure to x-rays essentially leads to a film that reflects the clear base of the film itself rather than any developed radiographic image.

In contrast, overexposure to radiation typically leads to a film that appears black due to excessive darkening of the film layer from too many x-ray photons. Exposure to light can fog the film, creating a generally cloudy appearance, but not a clear one. Lastly, incorrect developer temperatures can lead to underdevelopment or overdevelopment, but will not inherently render a film clear; instead, it tends to create varying degrees of density or artifacts. Thus, the situation that leads to a clear film is rooted in the lack of proper exposure or the premature use of fixer.