This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal System, Subject name: Radiology
Modality of choice for screening of bony metastases? 
Select and explain. 
A. Plain radiograph, B. CT, C. MRI, D. Bone scan
D: Bone scan
Answer: D: Bone scan 
Explanation: Ans DBone metastases can be seen at any site which maybe even far away from the primary as they spread by hematogenous route. So for their screening a modality which includes entire skeletal survey is employed - hence Bone scan is Best.