What is the main function of the NPC regarding the state budget?

The main function of the National People's Congress (NPC) regarding the state budget is to approve and monitor the state budget. This highlights the role of the NPC as the highest legislative body in China, which is responsible for examining and ratifying the state budget proposed by the government. The process involves reviewing the budget, ensuring it aligns with national priorities, and enabling oversight of how funds are allocated and spent.

This monitoring function is essential for accountability in a system where the executive branch, particularly the State Council, proposes the budget. The NPC's involvement helps to ensure that there is a legislative check on the executive's financial decisions. This is crucial in maintaining a balance of power and promoting transparency in financial management within the state.

The other options misrepresent the role of the NPC. Drafting the budget independently implies that the NPC has the authority to create the budget, which it does not; that responsibility lies with the government. Setting the budget without checks contradicts the needs for legislative oversight, and focusing solely on past expenditures would limit the NPC's function to retrospective analysis rather than proactive governance and oversight of future financial planning.