Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
Example: Who was the first American President?
Example solution: president of the united states
Example explanation: The question talks about the president of the USA.

Problem: What country in North Africa, bordered by Tunisia, Libya, Niger, Mali, Mauritania, Western Sahara, Morocco and the Mediterranean Sea, is the largest country on the Mediterranean, and the second largest on the African continent and in the Arab world?
Solution: sahara