Increasing which temperature will result in a film with increased density?

Increasing the development temperature during the film processing will result in increased density of the radiographic film. This is primarily because higher temperatures accelerate the chemical reactions that take place during the development stage. The developer's activity increases with temperature, leading to a more intense blackening of the silver halide crystals that have been exposed to radiation. As a result, more metallic silver is formed, which contributes to the overall density of the film.

In contrast, variations in fixer temperature, water bath temperature, or room temperature do not have the same direct impact on film density as development temperature does. Fixer temperature primarily affects the fixing process, which ensures that the unexposed silver halide crystals are removed, but it does not contribute to the density of the developed image itself. Similarly, adjustments in water bath and room temperatures do not inherently change how the film is developed, and instead are more related to maintaining the overall stability of the processing environment.