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
Which radiographic projection is most useful in examining stone of a submandibular duct 
Select and explain. 
A. Cross-sectional occlusal, B. OPG, C. Lateral oblique, D. PA view of mandible
A: Cross-sectional occlusal
Answer: A: Cross-sectional occlusal 
Explanation: None