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 rank of the peerage is directly below a duke?

Answer: duke


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: In 1969, who became the youngest woman ever to be elected to British Parliament?

Answer:
parliament of the united kingdom