Answer: Mechanical waves can be Longitudinal or Transverse.
Explanation: So... a mechanical wave is a kind of wave that is a oscillation of matter. Mechanical waves can also transfer energy. However, while it still can transfer over long distances, the wave is limited. it means that the oscillation material is limited. A mechanical wave can be a transverse wave or a longitudinal wave or a surface wave. but since there is only Longitudinal or Transverse that should be your answer.
A transverse wave, its a wave that particles move up and down.
A Longitudinal wave is a wave that moves back and forth.