Which of the following units is used to express a radiographer's whole-body effective dose?

The unit used to express a radiographer's whole-body effective dose is the Sievert. This unit is specifically designed to quantify the biological effect of ionizing radiation on human tissue, taking into account the type of radiation and the energy it deposits in the body. The Sievert reflects the potential damage that radiation can cause, which is critical for assessing health risks and ensuring safety in radiologic practices.

In this context, other units like the Curie are used to measure radioactivity, focusing on the decay rate of radioactive materials rather than the biological impact on the body. The Gray is a unit that measures absorbed dose, which is the amount of energy deposited in tissue, without accounting for the varying degrees of biological effects caused by different types of radiation. Roentgen, while historical and still used in some contexts, measures exposure to ionizing radiation in air and does not provide a direct measure of biological effect in human tissues like the Sievert does. Therefore, for assessing whole-body effective dose and the associated health risks from radiation exposure, the Sievert is the appropriate and scientifically supported choice.