**Question:** Palmar interossei is supplied by

A. Radial artery
B. Ulnar artery
C. Deep branch of ulnar artery
D. Superficial palmar arch

**Core Concept:** The palmar interossei muscles are a group of intrinsic hand muscles responsible for opposition and interception of the fingers. These muscles receive their blood supply from the palmar arch, which is a vascular structure in the palm.

**Why the Correct Answer is Right:** The palmar interossei muscles (carpal flexors) are supplied by the deep branch of the ulnar artery. The ulnar artery branches into the deep palmar arch, which then divides into several branches to supply the palmar interossei muscles.

**Why Each Wrong Option is Incorrect:**

A. Radial artery: The palmar interossei muscles are not supplied by the radial artery. The radial artery supplies the muscles of the dorsal wrist and hand, not the palmar muscles.

B. Ulnar artery: While the ulnar artery supplies the deep palmar arch and subsequently the palmar interossei muscles, the correct answer is the deep branch of the ulnar artery, not the ulnar artery itself.

C. Deep branch of ulnar artery: As mentioned above, the deep branch of the ulnar artery is responsible for supplying the palmar interossei muscles. The correct answer is the deep branch, not the deep branch of the ulnar artery.

D. Superficial palmar arch: The superficial palmar arch supplies the skin and superficial muscles of the palm, but not the palmar interossei muscles.

**Clinical Pearl:** Understanding the arterial anatomy of the hand is crucial for interpreting hand injuries and surgical interventions. Knowledge of the palmar arch and its branches can help in diagnosing and treating patients with hand injuries, as well as for planning surgical procedures involving the hand.