Final answer:
The greatest reduction of radiation exposure to a patient is achieved by increased collimation. This technique focuses the radiation beam to the area of interest, reducing unnecessary exposure to surrounding tissues, unlike increasing exposure time, focal-film distance, or milliamperage.
Step-by-step explanation:
The greatest reduction of radiation to the patient is achieved by A) Increased collimation. Collimation is the process of focusing the beam of radiation to a specific area, which not only improves image quality but also significantly reduces the exposure of surrounding tissues to radiation. This reduces the radiation dose to the patient by preventing unnecessary radiation from spreading to areas that are not being imaged.
Increased exposure time B), increased focal-film distance C), and increased milliamperage D) could actually increase the patient's exposure to radiation. Therefore, the correct answer is A) Increased collimation. For work environments dealing with radiation, protective measures include adequate shielding, maintaining a safe distance from radiation sources, and minimizing exposure time.