Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Example Input: Who released the albums Sentimental Journey, Goodnight Vienna, Bad Boy, Old Wave and Vertical Man between 1970 and 1999?
Example Output: vertical man

Example Input: The Battle of Poltava in 1709 was a victory by Peter the Great over which state?
Example Output: battle of poltava

Example Input: Although it was headquartered at Oak Ridge, TN, and the University of Chicago, what was the name of the WWII project that created the atomic bomb?
Example Output:
nuclear weapon