The statements are;
A) All waves travel at the same speed if no medium is present.
B) Electromagnetic waves require a medium, but mechanical waves do not.
C) All waves travel at the same speed through any medium.
D) Mechanical waves require a medium, but electromagnetic waves do not.
Answer:
Statement D is true.
Mechanical waves require a medium, but electromagnetic waves do not.
Explanation:
The two types of waves are;
Mechanical waves and Electromagnetic waves.
Mechanical waves require a medium, such as an atmosphere or water, to enable it transport its energy. For example sound waves occur when you clap and thereby distort the air around.
Whereas, Electromagnetic waves do not require a medium to enable it transport its energy. A good example would be light. Normally, Electromagnetic waves are usually formed when the electric field and the magnetic field are perpendicular to each other.
So electromagnetic waves can transmit without a medium because electric and magnetic fields can exist independently without a medium.
