What did the chinese nationalist do in 1938 to delay the advance of the japanese army?

They broke the barriers that held back the Yellow River to cause major flooding in the path of Japan's advance.

Chiang Kai-shek ordered the destruction of the walls that were constructed to contain the river.  It was done without warning to Chinese people in the regions, so that the Japanese army would be caught by surprise.  It also caught the Chinese people by surprise.  A half million were killed in the floods and around four million had to flee their homes and villages.  Such a costly act in their own territory showed just how determined the Chinese were not to let Japan overcome them.

the correct answer is d: "party organizers, volunteers, voters, and elected officials."

party organizers: individuals responsible for designing strategies in order to better execute the political campaign. this includes the candidate's public relations. volunteers: individuals responsible for raising awareness regarding the candidates running for office.voters: individuals who are convinced by volunteers that a particular candidate is the best option.elected officials: winning candidate and his elected team are a product of a successful political campaign.