Final answer:
The most extensive examination is a complete multisystem examination, which is more comprehensive than a single specialty examination as it covers multiple organ systems.
Step-by-step explanation:
The most extensive examination that encompasses a complete single specialty examination or complete multisystem examination is a complete multisystem examination. This is more comprehensive because it covers multiple organ systems, potentially including all of those that would be examined in individual specialty exams. For example, a complete multisystem examination might include the Neurological Exam, which consists of the Mental Status Exam, the Cranial Nerve Exam, the Sensory and Motor Exams, and the Coordination and Gait Exams, as well as similar assessments for other systems of the body.