instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
Who sang the theme tune to the James Bond film Die Another Day?
answer:
die another day


question:
Which engineer built the Menai Suspension Bridge and the Caledonian Canal?
answer:
menai suspension bridge


question:
Which is the tallest steel arch bridge in the world?
answer:

arch bridge