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

Which rock group was founded in Seattle in 1994 by David Grohl after the break-up of Nirvana?

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
nirvana