Final answer:
Electromagnetic waves, which consist of perpendicular electric and magnetic fields to the direction of wave travel, are best described as transverse waves with polarized directions.
Step-by-step explanation:
The type of wave that best describes an electromagnetic wave where an electric field exists perpendicular to a magnetic field, and both fields are perpendicular to the direction of travel of the wave is a transverse wave. In electromagnetic waves, the oscillations for the electric field (E) and magnetic field (B) are perpendicular to the direction in which the wave is moving. It is a distinctive feature of electromagnetic waves, such as light, to consist of these perpendicular oscillating fields, with polarization being the attribute that describes the wave's oscillations having a definite direction relative to the direction of wave propagation. The direction of polarization is defined parallel to the electric field for electromagnetic waves.