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: Medicine
[{'content': 'The commonest cause of death in a patient with primary amyloidosis is - \nSelect and explain. \nA. Renal failure, B. Cardiac involvement, C. Bleeding diathesis, D. Respiratory failure', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]