This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Radiology
Radiation dose safe in pregnancy is 
Select and explain. 
A. 1 rad, B. 5 rads, C. 50 rads, D. 500 rads
B: 5 rads
Answer: B: 5 rads 
Explanation: (Ref: Farr&;s physics for medical imaging 2e,39)