The term "collimation" refers to which of the following?

Collimation refers to the process of narrowing the radiation beam to focus it more precisely on the area of interest during imaging procedures, such as X-rays. By restricting the beam, collimation minimizes radiation exposure to surrounding tissues and improves image quality by reducing scatter radiation, which can cause blurring. This precise targeting helps ensure that the appropriate area is examined while protecting the patient from unnecessary radiation.

The function of collimation is crucial in achieving optimal diagnostic images and maintaining safety standards in radiology practices. In contrast, widening the beam, increasing exposure time, or decreasing film size would not align with the primary purpose of collimation, which is to control and fine-tune the radiation beam for accuracy and reduced exposure.