In which phase is a systems acceptance test plan developed and documented? （）

A. Prepare, Plan, Create, Implement, Operate, and Improve
B. Prepare, Plan, Design, Implement, Operate, and Optimize
C. Prepare, Plan, Design, Apply, Operate, and Manage
D. Prepare, Plan, Design, Implement, Operate and Manage

A.Prepare
B.Plan
C.Design
D.Operate

A. reset of the primary supervisor
B. manual switchover from standby to active supervisor
C. manual switchover from active to standby supervisor
D. automatic switchover from active to standby on primary supervisor failure