启用销售订单缺货预警，已分配销售订单所指的销售订单是什么状态？（）

A.保存时

B.审核未关闭

C.已关闭

D.已冲减

The settlement price for a futures contract is:()

A. an average of the trade prices during the ’ closing period’ 

B. the price of the last trade of a futures contract at the end of the trading day. 

C. the price at which all trades over a certain period are executed.