Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Q: What is the Army equivalent to a Group Captain in the R.A.F.?

A: british army
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Q: 'Edward Lewis' and 'Vivian Ward' were the principal characters in which popular 1990 film?

A: edward lewis
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Q: In Greek myth, who was the son of Agamemnon and Clytemnestra, who killed his mother to avenge his father's death?

A:
agamemnon
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