The correct answer is 4. The clinician should avoid performing the high-thrust technique until the vertebral artery is cleared. Waiting until the patient has sufficient cervical range of motion to perform the test would be ideal but not practical given the time that it might take and does not directly answer the question. Performing the test in the patient's available range of motion would be prudent, providing that the patient is not passively placed in positions beyond those ranges, which would be difficult to determine and, therefore, potentially dangerous.