Which of the following 802.11 standards can operate at both 2.4 GHz and 5.0 GHz?（）

A. Orange/white, orange, green/white, blue, blue/white, green, brown/white, brown
B. Blue, blue/white, orange/white, orange, brown/white, brown, green/white, green
C. Green/white, green, orange/white, blue, blue/white, orange, brown/white, brown
D. Orange/white, orange, brown/white, brown, green/white, green, blue, blue/white

A. Biometric device
B. Mouse
C. Camcorder
D. Infrared scanner

A.Floppy
B.SCSI
C.IEE1394
D.IDE