This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Radiology Q Bank, Subject name: Radiology
Which one of the following modalities is maximum dangerous to 10 weeks pregnant lady? 
Select and explain. 
A. CT CHEST, B. SPECT, C. CT Abdomen, D. Bone-scan
C: CT Abdomen
Answer: C: CT Abdomen 
Explanation: CT scan Typical effective dose (mSv) for various investigations: Chest X-ray: 0.02CT Head: 2.3CT Chest: 8CT Abdomen / Pelvis: 10Bone scan (Tc-99m): 4