Answer:
B. A high-frequency sound
Explanation:
The ability to localize sound is a crucial function of the auditory system, and it relies on several cues, including interaural time differences (ITD) and interaural level differences (ILD).
Interaural Level Differences (ILD)
- High-Frequency Sounds: For high-frequency sounds, the wavelength of the sound waves is relatively short. When these waves encounter the head, they create a "sound shadow" on the opposite side, resulting in a difference in sound pressure level (loudness) between the two ears. This difference is known as the interaural level difference (ILD).
- Localization: The auditory system uses these ILDs to determine the direction from which the sound is coming. High-frequency sounds, therefore, have more pronounced ILDs due to the head shadow effect, making it easier for the brain to localize the source of the sound.
Why Not Other Types?
- Low-Frequency Sounds: Low-frequency sounds have longer wavelengths that can bend around the head more easily, leading to smaller ILDs. The brain primarily relies on interaural time differences (ITD) to localize low-frequency sounds.
- Sudden Onset Sounds: The suddenness of a sound's onset can be detected by both ILDs and ITDs, but it does not specifically help in determining the frequency of the sound.
- Familiar Sounds: Familiarity with a sound is related to memory and recognition, which do not primarily depend on ILD.
Conclusion
High-frequency sounds are more effectively localized using interaural level differences because their shorter wavelengths result in more significant differences in loudness between the ears due to the head shadow effect. This is why the correct answer is:
B. A high-frequency sound