You can play this easy or hard. I'll let you choose.
Easy – for those who are geography-based, this one is more likely to appeal to you. You need only name the city in which each team is based.
Hard – for those who are avid fans of the Champions League, you may name each team that competed this year.
I understand that people may dabble with both opportunities, but that is ok. The test is only as hard as you make it.