Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
One example is below.
Q: Who was the first American President?
A: president of the united states
Rationale: The question talks about the president of the USA.
Q: Because of his advocation for the use of direct current (DC) for electric power distribution, Thomas Edison developed a bitter rivalry with which other genius who advocated alternating current (AC)?
A:
alternating current