设y1=40.9,y2=80.48,y3=-1.5,则( )
A.y3>y1>y2 B.y2>y1>y3
C.y1>y2>y3 D.y1>y3>y2
D
[解析] y1=21.8,y2=21.44,y3=21.5,
∵y=2x在R上是单调递增函数,∴y1>y3>y2.