Whichdefinitionbestdescribesthestafftrainingservicecomponentwithintheimplementphase？Selectexactly1answer（s）fromthefollowing：（）。

A.improvingthenetworkmanagementsystemandtheperformanceandfunctionalityofinfrastructureoperations
B.providingastep-by-stepplanthatdetailstheinstallationandservice-commissiontasksrequiredinordertocreateacontrolled-implementationenvironmentthatemulatesacustomernetwork
C.developingandimplementingatrainingplanusingclasses，workshops，orc-learningcourses
D.compilingatrainingmanualforuseinongoingoperations
E.reducingtheriskofdowntimeduetofacilities-relatedproblems