In securities exchange markets, a member who executes stop loss or stop buy orders when the specified price occurs is most likely a:（）

A. floor broker.

B. market maker.

C. commission broker.

拌合楼按工艺流程分层布置，分为进料、贮料、配料、拌合及出料共五层，其中( )是全楼的控制中心，设有主操纵台。

A．进料层
B．配料层
C．贮料层
D．拌合层