Which technique can help reduce the amount of scattered radiation reaching the film?

Using a filtered X-ray beam is effective in reducing the amount of scattered radiation reaching the film because filtering selectively removes lower-energy X-rays that contribute to unnecessary radiation exposure without enhancing the diagnostic quality of the radiograph. These lower-energy X-rays are more likely to be scattered in the material being radiographed, thus leading to an increase in background noise and a decrease in the overall image quality. By employing a filtered X-ray beam, the image contrast improves, and the risk of scatter radiation is minimized, enhancing the clarity and accuracy of the radiographic results.

Options focusing on increasing exposure time, reducing film sensitivity, or using an unfiltered X-ray beam do not address the issue of scattered radiation effectively. Increasing exposure time could lead to more scatter reaching the film, while reducing film sensitivity may only result in reduced image quality overall. An unfiltered X-ray beam would include more low-energy photons, thereby contributing to an increase in scatter and decreased image quality.