To determine the most suitable question for the property column instead of the letter X, we should consider the nature of electromagnetic and mechanical waves.
- Electromagnetic waves do not require a medium and can travel through a vacuum, whereas mechanical waves require a medium (like air, water, or solid materials) to propagate.
Given the context of electromagnetic and mechanical waves, the question that most directly addresses a fundamental property distinguishing these types of waves would be:
How does this wave transfer matter?
This question relates to the nature of mechanical waves (which transfer matter) versus electromagnetic waves (which do not transfer matter).