Answer:
Mechanical waves
Explanation:
As per the criteria of wave propagation we can divide the waves into two parts
1). Mechanical waves : Those waves which require medium to travel then it is known as mechanical waves
examples: Sound waves, String waves etc
2) Non Mechanical waves: Those waves which do not require any medium to propagate is known as non mechanical waves.
Examples : Light waves, electromagnetic waves etc
So here correct answer would be Mechanical waves
