Which of these phases comprises post-project support activities： activities that happen after a project is successfully implemented and handed off？（）

A.plan
B.design
C.prepare
D.operate

A.reduced operating costs， due to a consistent framework for making necessary changes in an efficient and accountable manner
B.greater accuracy， completeness， and timeliness of network configuration information
C.notification provided to interested parties regarding problems that have been identified， and a system that scales with customer requirements
D.improved system service quality and fewer disruptions

A.reduce unnecessary disruption， delays， rework， and other problems by establishing test cases for use in verifying that the system meets operational， functional， and interface requirements
B.improve its ability to make sound financial decisions by developing a business case based on its business requirements and establishing a basis for developing a technology strategy
C.reduce operating costs and limit change-related incidents by providing a consistent and efficient set of processes
D.improve the return on investment and hasten migration by identifying and planning for necessary infrastructure changes and resource additions， as well as reduce deployment costs by analyzing gaps early in the planning process to determine what is needed to support the system