Final answer:
A(n) budget describes the projected income and expenses for a specific time period, and may be zero-based or arbitrary.
Step-by-step explanation:
A(n) budget describes the projected income and expenses for a specific time period. It provides a detailed breakdown of the expected revenue and costs. One type of budget is a zero-based budget, which requires each item to be justified from scratch every period. Another type is an arbitrary budget, which is based on estimations and previous experience, but lacks a rigorous justification process. The remaining options, surplus and ad hoc, are not types of budgets.