A 17-year-old boy is brought to the emergency department 5 hours after he sustained a stab wound to the left dorsal forearm. on physical examination, he is unable to extend the thumb and metacarpophalangeal joints. exploration of the wound for repair of a presumed nerve injury is planned. proper exposure of the nerve is between which of the following muscle groups?
A) Brachialis and triceps
B) Brachioradialis and extensor carpi radialis longus (ECRL)
C) Extensor carpi radialis brevis (ECRB) and ECRL
D) Extensor digitorum communis and ECRB
E) Flexor carpi radialis and pronator teres