TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Which of these was the title of Bobby Darin's first million selling single?

SOLUTION: bobby darin

PROBLEM: What was Bon Jovi's first UK top ten hit single?

SOLUTION: bon jovi

PROBLEM: Which city, previously the Roman town of Vindobona, became the capital of the Duchy of Austria in 1156 and the capital of Hapsburg power base in the 13th century?

SOLUTION:
austria