This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thromboembolism and Fat Embolism Syndrome, Subject name: Medicine
[{'content': 'A patient presents with fracture of femur. On 3rd day of admission he develops breathlessness. Most probable diagnosis is? \nSelect and explain. \nA. A.R.D.S, B. P.A.H, C. Pulmonary embolism, D. Neurogenic shock', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Fracture of femur- Cause immobilization | Stasis in calf veins | Thrombus formation- Retrograde spread- Pulmonary embolism', 'role': 'assistant'}]