Which type of X-ray film has a higher speed?

The choice indicating that films with large grain size have a higher speed is accurate due to the relationship between grain size and sensitivity in radiographic films. In film-based radiography, the term "speed" refers to the film's sensitivity to radiation; higher-speed films are more sensitive and can produce images with shorter exposure times.

Films with larger grains allow for a greater degree of light or radiation to be captured, enhancing the film's responsiveness. This effectively means that less exposure time is required to produce an image of acceptable quality. As a result, larger grain films can capture equivalent images more quickly compared to those with finer grains, which need more exposure to achieve similar results due to their reduced sensitivity.

Understanding this concept is crucial for selecting the appropriate film type based on the requirements of a radiographic inspection, such as the desired image clarity and the necessary exposure time.