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: Pathology
[{'content': 'Edema may be caused by any of the following, EXCEPT: \nSelect and explain. \nA. An increase in the plasma protein concentration, B. An increase in the capillary hydrostatic pressure, C. An increase in the capillary permeability, D. Lymphatic obstruction', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Oedema is caused by mechanisms that interfere with normal fluid balance of plasma, interstitial fluid and lymph flow.\nThe following mechanisms may be operating singly or in combination to produce oedema:\n\nDecreased plasma oncotic pressure.\nIncreased capillary hydrostatic pressure.\nLymphatic obstruction.\nTissue factors (increased oncotic pressure of interstitial fluid, and decreased tissue tension).\nIncreased capillary permeability.\nSodium and water retention.\n\nMohan H. Textbook of pathology. Jaypee Brothers Medical Publishers; 2015. Edition 7. Page 80', 'role': 'assistant'}]