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: With which song did Swedish pop group Abba win the 1974 Eurovision Song Contest?

Answer: abba


Question: What is the SI unit of capacitance?

Answer: capacitance


Question: The 1798 Battle of the Nile is also known as the Battle of which Bay?

Answer:
battle of the nile