This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
Investigation to diagnose stage-I carcinoma breast – 
Select and explain. 
A. B/L mammogram, B. X–ray chest, C. Bone scan, D. Liver scan
A: B/L mammogram
Answer: A: B/L mammogram 
Explanation: None