Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
--------
Question: In which range of mountains are the two highest peaks Aconcagua and Ojos Del Salado?

Answer: aconcagua


Question: Which late 17th and early 18th century British architect designed Brighton Pavilion, Marble Arch, and the plan for London's Regents Park?

Answer: royal pavilion


Question: Of which king was Eleanor of Castile queen?

Answer:
eleanor of castile