Answer : The correct option is, (b) longitudinal wave
Explanation :
Longitudinal waves : It is defined as the waves in which the particles of the medium move in the direction of the wave.
Transverse wave : It is defined as the waves in which the particles of the medium travel perpendicularly to the direction of the wave.
Surface wave : It is defined as a combination of transverse and longitudinal waves.
From the given image we conclude that, this illustration depict the longitudinal wave because the particles of the medium move in the direction of the wave.
Hence, the correct option is, (b) longitudinal wave