Which exposure setting will produce a radiograph with the least amount of motion blur?

To minimize motion blur in a radiograph, it's crucial to understand the relationship between milliamperage (mA) and exposure time (seconds). Motion blur occurs when there is movement during the exposure, and shorter exposure times reduce the possibility of this occurring.

In this case, the option providing the shortest exposure time, paired with a reasonably high mA, is the one that results in the least amount of motion blur. The chosen option features 420 mA with an exposure time of 0.001 seconds, which is extremely brief. The combination of high mA and a very short exposure time ensures that the image captured is less likely to show any blur due to patient or subject movement.

While other choices have relatively high mA settings, their longer exposure times increase the risk of motion blur. For example, the first choice has a longer exposure time of 0.0025 seconds, which, although short, is still longer than the 0.001 seconds of the correct choice. Therefore, the effective reduction in exposure time is critical for preventing motion blur.