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 plays Isobel Crawley in the UK television series 'Downton Abbey'?

Answer: downton abbey

Question: In 1864, the Dale Dyke Dam burst while being filled, leading to the death of 240 people in which British city?

Answer: dale dike reservoir

Question: Bridgetown is the capital city of which island nation?

Answer:
bridgetown