下列哪种数据库系统更适合于在大、中型计算机系统上使用？（）

A.数据库存取功能模块
B.数据库存储管理功能模块
C.数据库运行处理功能模块
D.数据库维护功能模块

A．SELECT S#，SNAME FROM S WHERE S# = (SELECT SS# FROM SC WHERE C# = 'C2' )
B．SELECT S#，SNAME FROM S，SCWHERE S# = SS# AND C# = 'C2'
C．SELECT S#，SNAME FROM S，SC WHERE S# = SS# AND C# = 'C2' ORDER BY S#
D．SELECT S#，SNAME FROM S WHERE S# IN (SELECT SS# FROM SC WHERE C# ='C2' )