Within a resource-plan definition, what differentiates a top-level plan from a subplan?（）

A. subplan has the PLAN_SUB parameter value set to SUB

B. top-level plan has the GROUP_OR_PLAN parameter set to the name of the subplan in the resource-plan definition

C. There is no difference in the resource-plan definition

D. subplan always has the CPU_MTH parameter value set to RATIO

E. The string TOP_LEVEL is appended to the name of top-level resource plans