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 is due to- \nSelect and explain. \nA. Increased capillary osmotic pressure, B. Decreased lymph flow, C. Decreased hydrostatic pressure in capillaries, D. Both of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pathogenesis of edema\nFollowing conditions can cause edema :-\n1) The increased hydrostatic pressure of capillaries, e.g. in CHF or DVT.\n2) Decreased plasma osmotic pressure of capillaries: It results from Hypoproteinemia. When\xa0total plasma protein is below 5 gm/dl (normal 6-8 gm/dl) or albumin is below 2-5 gm/dl (normal 3.5-5 gm/dl) edema takes place. Conditions causing hypoproteinemia are nephritic syndrome, liver cirrhosis, protein-losing enteropathy, and PEM.\n3) Defective removal of interstitial fluid by lymphatics: It is due to lymphatic obstruction, which\xa0may be inflammatory, neoplastic, post-surgical and post-irradiation.\n4) Increased vascular permeability: It occurs in acute and chronic inflammation, and during\xa0angiogenesis (new vessels are leaky).\n5) Sodium (salt) and water retention: The conditions responsible for this type of edema are ARF, acute glomerulonephritis, renal hypoperfusion, and increase renin angiotensin aldosterone system\n(RAAS) activity.', 'role': 'assistant'}]