Please answer the following question: Fact 1: Hydropower requires damming a river. Fact 2: Hydropower is a renewable, economical source of electricity. Given the two facts above, answer the question "what does a renewable, economical source of electricity require?" with the following options: - damming a river - power stations - freezing h2o - electricity - burning fossil fuels - hydrogen and oxygen - sunlight - nuclear meltdowns
A:
damming a river