What type of budgeting relies on input from those directly involved in the processes?

Activity-based costing is the correct choice for budgeting that incorporates input from those directly involved in processes. This approach focuses on identifying and analyzing the various activities within an organization and assigning costs based on the actual consumption of resources by these activities. By engaging individuals who perform the activities, this method ensures that budgeting reflects real operational insights and the true costs associated with producing products or services. It emphasizes collaboration and accurate data collection from employees, which enhances budget accuracy and effectiveness.

The other approaches generally do not rely on the direct input of those engaged in daily operations. Top-down budgeting is typically driven by upper management, making decisions based on broader strategic goals rather than the input from lower-level employees. Meanwhile, zero-based budgeting requires justification for all expenses, starting from a "zero base," which may not include direct operational input as a primary influence in the budgeting process. Incremental budgeting adjusts prior budgets based on historical trends, often neglecting the specific insights that operational staff could provide.