In Assessing the Severity of a Radiological Hazard, It Is

In assessing the severity of a radiological hazard, it is expedient to compare the level of exposure to the background radiation from the environment. A whole-body X-ray computed tomography scan (CT scan) produces an exposure of about 10 mSv (milliSieverts) compared to an annual background radiation exposure of approximately ________

A) 0.003 mSv.
B) 0.03 mSv.
C) 0.3 mSv.
D) 3 mSv.
E) 30 mSv.