Final answer:
The patient's Glasgow Coma Scale (GCS) score is 2
Step-by-step explanation:
The Glasgow Coma Scale (GCS) is used to assess the level of consciousness in a patient. It evaluates eye-opening response, verbal response, and motor response. Based on the information provided, the patient only opens his eyes to pain, moans, and withdraws, indicating an eye-opening response of 2 on the GCS.