What document authorizes changes to the project within the contract's general scope?

The change order is the correct answer because it is a formal document issued to authorize modifications to the original contract's scope, cost, or schedule. It serves as an agreement between the owner and the contractor that outlines the changes to be made and any adjustments to the project timeline or budget that may accompany those changes. Change orders are essential in project management as they help maintain clarity between all parties regarding the modifications being made and the reasons behind them.

While other terms like work order, modification contract, and supplemental agreement may also relate to project changes, they do not have the same specific legal and procedural implications as a change order. A work order typically refers to a request for work or a task to be performed but does not necessarily authorize changes to the overall project scope. A modification contract can refer to a more comprehensive alteration of a contract but is less commonly used in routine project adjustments. A supplemental agreement may involve additional terms but isn't specifically tied to changes in project scope like a change order is.