Final answer:
The ski slope hearing loss requires the largest vent in a hearing aid.
Step-by-step explanation:
The hearing loss that requires the largest vent is the ski slope hearing loss. This type of hearing loss is characterized by a significant drop in the ability to hear high-frequency sounds while still having some level of hearing in the lower frequencies. Because of the specific pattern of this type of hearing loss, a larger vent is needed in the hearing aid to allow the low-frequency sounds to pass through without amplification while still providing amplification for the high-frequency sounds.