Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
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Question: Which female gymnast won Gold Medals in the Balance Beam and Floor Exercise events in the 1972 Summer Olympics?

Answer: 1972 summer olympics

Question: Which American actor and singer has joined Amanda Holden as one of the judges on the current series of 'Britain's Got Talent'?

Answer: britain's got talent

Question: Center, Offensive guard, Offensive tackle, Tight end, Wide receiver, Fullback, Running back, Quarterback, Defensive end, Defensive tackle, Nose guard, Linebacker, Cornerback, Safety, Nickelback and Dimeback are positions in which sport?

Answer:
guard