Analysis of test questions: ① ② The options are correct and in line with the meaning of the questions. The practice of the Central People's Government in the problem is helpful to standardize the administrative behavior of the government and its staff, improve the government's credibility, better protect citizens' right to know and supervise, and facilitate citizens to supervise the government, so it is chosen. The views of options ③ and ④ are wrong. The central government's approach is conducive to the supervision of government power, but it cannot be balanced. There is no separation of powers in China, and there are no checks and balances between powers. The practice of the central government in the topic is not the key to building a service-oriented government, so it is excluded.