Final answer:
Damage to the brachial plexus (C5-C7) affects nerves that supply the arm, impacting such nerves as the radial, axillary, ulnar, and median nerves.
Step-by-step explanation:
Damage to the brachial plexus affecting spinal nerves C5 to C7 will impact the anatomical area and nerves supplying the arm. Specifically, these nerves are responsible for the reorganization of nerve fibers that give rise to nerves such as the radial nerve, axillary nerve, ulnar nerve, and the median nerve. The radial nerve, originating from this plexus, extends down the arm, while the axillary nerve branches to the armpit region. Similarly, the ulnar and median nerves are also paralleling the radial nerve and play a crucial role in the forearm and hand movements and sensations.