This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Musculoskeletal Radiology, Subject name: Radiology
What is the abnormality shown in this shoulder Radiograph? 
Select and explain. 
A. Anterior Dislocation Of Shoulder, B. Posterior Dislocation Of Shoulder, C. Chondrosarcoma, D. Simple Bone cyst
B: Posterior Dislocation Of Shoulder
Answer: B: Posterior Dislocation Of Shoulder 
Explanation: Electric Bulb/Light Bulb Appearance on Shoulder Radiograph Is suggestive of posterior Dislocation of Shoulder.