Which one of the following is not considered as a type of waves regarding how waves travel?

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Regarding how waves travel, there are two types of waves. They are longitudinal and transverse waves. When substances of the medium and waves move perpendicular to each other, these type of waves are called transverse waves. A water wave is an example of a transverse wave because water moves up and down while wave moves through the surface of the water. In longitudinal waves, on the other hand, substances of the medium and waves move parallel to each other. Sound is a good example of a longitudinal wave. Compressional wave is another name for a longitudinal wave. As it can be seen in the figure, Longitudinal spring waves have compression and rarefaction areas, so this type of waves are called Compressional Waves. On the other hand, there is no wave type called vertical waves.
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Which One of the Following Is Not Considered as a Type