You are given a concept, and a list of answers. You should generate a question about the concept that leads to the given answer(s).
--------
Question: concept: Barack Obama  answers:  ['Dreams from My Father']

Answer: what do barack obama do as a president?


Question: concept: Isaac Newton  answers:  ['Physicist']

Answer: what is isaac newton famous for?


Question: concept: Abraham Lincoln  answers:  ['""The Emancipation Proclamation...can remind us in 2013 of all the mistakes we never want to commit again but it can also motivate us to fulfill to an ever greater degree the definitive freedom-sustaining and life-enhancing principles of democracy in living action.""']

Answer:
when did abraham lincoln free the slaves?