原型模型是增量模型的另一种形式，用于需求分析阶段的模型是（）

A．SELECT S#FROM SC
WHERE C#="C2" AND Grade IN
(SELECT Grade FROM SC WHERE C#="C2")
B．SELECT S# FROM SC
WHERE C#="C2" AND Grade＞=
(SELECT Grade FROM SC WHERE C#="C2")
C．SELECT S# FROM SC
WHERE C#="C2" AND Grade＞=ALL
(SELECT Grade FROM SC WHERE C#="C2")
D．SELECT S# FROM SC
WHERE C#="C2" AND Gtade NOT IN
(SELECT Grade FROM SC WHERE C#="C2")

A．T₁（n）=n+nlog_n
B．T₂（n）=2n+nlog_n
C．T₃（n）=n²-log_n
D．T₄（n）=n+100log_n