Final answer:
The correct answer is b. The ulnar artery supplies the little finger side of the arm and palm of the hand. It bifurcates from the brachial artery at the elbow, runs alongside the ulna, and contributes to the superficial and deep palmar arches providing blood to the specified region.
Step-by-step explanation:
The brachial artery, as it approaches the coronoid fossa at the elbow, bifurcates into two main arteries: the radial artery and the ulnar artery. The radial artery parallels the radius bone and the ulnar artery parallels the ulna. The ulnar artery is responsible for supplying blood to parts of the lower arm and, most notably, to the little finger side of the arm and palm (the ulnar side).
As it reaches the carpal region, the ulnar artery gives off smaller branches and eventually fuses with the radial artery to form the superficial and deep palmar arches. These palmar arches are further responsible for supplying blood to the hand and digital arteries which provide circulation to the digits of the hand. Therefore, the ulnar artery is the primary vessel for the area in question.