Which best describes how cleisthenes's reforms in athens set important precedents for later governments?

It's because He widened the part played by ordinary citizens in Athens’ government. 
Cleisthene  was known as the reformer athen's constitutiton in 500 BC. This reformation marked the beginning of the Athenian Democracy, where the people could be involved in the decision making process by the Government. His method is adopted by almost all modern countries today.