Milliamperage (mA) and time determine what?

• A. The number of X-rays delivered and the darkness of the image
• B. The sound produced by the machine
• C. The physical size of the X-ray beam
• D. The chemical composition of developer

Answer: (A)

The key idea is that mA and exposure time control how much X-ray energy is produced. This quantity directly determines how dark the radiographic image will be: more X-rays reaching the film or sensor makes the image darker, while fewer X-rays makes it lighter. The beam’s penetrating power (quality) is mainly set by kilovoltage peak, not by mA or time, so adjusting mA or time changes darkness, not the energy of the photons. The other options don’t fit because sound is not affected by exposure settings, the physical size of the X-ray beam is set by collimation and geometry rather than mA/time, and the developer’s chemical composition is a fixed property, with exposure influencing the image appearance but not altering the developer itself.