The radiolucent canal coursing through the body of the mandible on a panoramic radiograph, transmitting a major branch of the trigeminal nerve, is the:

The mandibular canal houses the inferior alveolar nerve, artery, and vein as they course through the mandibular body before the nerve exits anteriorly at the mental foramen. It's a key landmark to identify before extractions, implant planning, or third molar surgery in this region.