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: Who composed the opera 'Albert Herring' in 1947?

Answer: albert herring


Question: Who married the woman who was to become Queen Beatrix of the Netherlands, on 10 March 1966?

Answer: beatrix


Question: Following which singer's death last year did the album 'Back To Black' top the UK charts for three weeks?

Answer:
back to black