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': 'Best test to detect iron deficiency anemia in a community with low prevalence of iron deficiency is: March 2013 \nSelect and explain. \nA. PCV, B. Iron binding capacity, C. Serum Iron, D. Serum ferritin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. Serum ferritin In the appropriate clinical setting, a smear showing hypochromia and microcytosis is adequate for the diagnosis. When more specific tests are needed, a positive diagnosis can be made from low levels of ferritin, and a low serum iron level in association with an elevated total iron binding capacity. Iron deficiency anemia (IDA): Commonest cause of anemia in India Increased iron absorption is seen in: Iron deficiency anemia, pregnancy, hypoxia, acidic pH of stomach, ferrous iron salts Causes of IDA: Hookworms, celiac sprue, carcinoma colon Features diagnostic of IDA: Decreased serum ferritin, increased TIBC Earliest sign of IDA: Decrease in serum ferritin Most sensitive and specific test for diagnosing IDA: Serum ferritin levels Hypochromia may be preceded by microcytosis', 'role': 'assistant'}]