Electromagnetic waves are transverse in nature as is evident by

Find the one that best describes the transverse nature of electromagnetic waves by recalling the fundamental ideas of electromagnetic wave diffraction, diffraction of electromagnetic wave, and polarisation of electromagnetic wave.

We are aware that diffraction and interference account for the electromagnetic wave's wave character.
In interference, two waveforms combine to create a new wave that may have a different amplitude.
And in Diffraction, a tiny bending of light is seen when it travels around an object's edge.
However, with polarisation, an electromagnetic wave's vibration is constrained in a direction perpendicular to the wave's propagation.
Polarization therefore explains why electromagnetic waves are transverse in nature.

Thus, it explains why EM waves are transverse.

The correct answer is option A) Polarization