Answer:
B. A pipe's length is equal to 1⁄2 of the wavelength of the sound waves produced by a tuning fork vibrating over one end of the pipe that's open to the air at both ends.
Explanation:
Resonance is a phenomenon that is produced when a body that is capable of vibrating is subjected to a periodic force, whose period of vibration is equal to the period of vibration of said body. In this case, the body vibrates, progressively increasing the amplitude of its movement after each of the successive actions of the force.
An example of this is taking two tuning forks that emit a sound of the same frequency and are placed close to each other, when one is vibrated, the other tuning fork emits the same sound, this is because the sound waves it produces the first press through the air to the second.
