TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: The Byzantine Empire is the term used since the 19th century to describe the Roman Empire of the Middle Ages, centred on its capital, where?

SOLUTION: byzantine empire

PROBLEM: In which Indian city is Eden Gardens, the second largest test cricket ground in the world?

SOLUTION: eden gardens

PROBLEM: Which British female swimmer won a silver medal at the 1980 Moscow Olympic Games for the 400 metre medley?

SOLUTION:
silver medal