The correct order of electromagnetic spectrum with decreasing frequency is:
1
Microwaves, Radiowaves, Infrared rays, Ultraviolet rays, X–rays
2
Radiowaves, Infrared rays, Ultraviolet rays, Microwaves, X–rays
3
X–rays, Infrared rays, Microwaves, Radiowaves, Ultraviolet rays
4
X–rays, Ultraviolet rays, Infrared rays, Microwaves, Radiowaves