What is the relationship between rem and millirem?

The correct answer is based on the definitions of the units of measurement used in radiation dosimetry. A rem (roentgen equivalent man) is a unit that measures the amount of ionizing radiation absorbed by human tissue and its biological effects. The millirem is a subunit of the rem, with the prefix "milli-" indicating one-thousandth of the base unit.

Therefore, since 1 rem is equal to 1000 millirem, this relationship is a direct conversion based on the metric system, which facilitates understanding and calculation of radiation exposure levels. This means that if an individual is exposed to 1 rem of radiation, that exposure can also be expressed as 1000 millirem, making it easier to communicate and manage in practical terms, especially when dealing with smaller doses commonly encountered in various fields such as medical applications or environmental monitoring.

The other options do not accurately reflect the correct conversion relationship between rem and millirem, which is crucial for properly assessing and managing radiation exposure.