Determine the topic of the question-answer pair. Question: "how many presidents have been assassinated?"; Answer: "Four sitting presidents have been killed: Abraham Lincoln (the 16th President), James A. Garfield (the 20th President), William McKinley (the 25th President) and John F. Kennedy (the 35th President)."? Topic:
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Answer: List of United States presidential assassination attempts and plots

Determine the topic of the question-answer pair. Question: "who is the group enigma?"; Answer: "Enigma is an electronic musical project founded in Germany by Michael Cretu , David Fairstein and Frank Peterson in 1990."? Topic:
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Answer: Enigma (musical project)

Determine the topic of the question-answer pair. Question: "what makes a dwarf planet?"; Answer: "More explicitly, the International Astronomical Union (IAU) defines a dwarf planet as a celestial body in direct orbit of the Sun that is massive enough for its shape to be controlled by gravitation , but that unlike a planet has not cleared its orbital region of other objects."? Topic:
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Answer:
Dwarf planet