The project budget has been finalized．Additional work has been discovered that was not planned for in the budget or project scope．Where could the found to cover the newly discovered work item

A．Contingency reserv

B．Project profi

C．Management reserv

D．Abandoning fun

网络操作系统提供的通信服务有：工作站与工作站之间的对等通信，及 【9】 之间的通信服务等功能。