You are given a question. You need to detect which category better describes the question. A question belongs to the description category if it asks about description and abstract concepts. Entity questions are about entities such as animals, colors, sports, etc. Abbreviation questions ask about abbreviations and expressions abbreviated. Questions regarding human beings, description of a person, and a group or organization of persons are categorized as Human. Quantity questions are asking about numeric values and Location questions ask about locations, cities, and countries. Answer with "Description", "Entity", "Abbreviation", "Person", "Quantity", and "Location".
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Question: What is the quantity of American soldiers still unaccounted for from the Vietnam war ?

Answer: Quantity


Question: What causes headaches ?

Answer: Description


Question: What two presidents of the U.S. published books of poetry ?

Answer:
Person