This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Shoulder and arm injuries, Subject name: Orthopaedics
[{'content': 'Vascular sign of Narath is positive in which of the follwoing ? \nSelect and explain. \nA. Posterior dislocation, B. Central dislocation, C. Anterior dislocation, D. Lateral dislocation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Vascular sign of Narath: Patient in supine Palpate femoral aery in femoral canal Positive in hip dislocation - not palpable In fracture neck of femur - feeble pulsation Ref: maheswari 9th ed ohopedics', 'role': 'assistant'}]