Which rays are not the portion of electro-magnetic spectrum?

Which rays are not the protion of electromagnetic spectrum?

What is electro magnetic spectrum?

The visible portion of the electromagnetic spectrum is

What is the frequency range of the visible portion of the electromagnetic spectrum?

Which of the following rays and waves do not belong to electromagnetic spectrum ? alpha rays , X rays, Ultraviolet rays , Radiowaves , Cathode rays , Ultrasonic waves, Infrared rays and Microwaves

What is electro-magnetic induction?

A ray is a portion of