There can be more than one. For example, if stakeholders feel the entire DAO budget is too large they can create a burn proposal which burns half and vote it to the very top. The remaining half will flow down through the others proposals, effectively cutting the total budget. Or similarly if stakeholders feel that too much is being paid out now but perhaps should be saved in the treasury for later, a return proposal for part of the budget can be voted to the very top.

There are other combinations possible.