Where do osteocytes reside?

Correct Answer: D

Rationale: Osteocytes live in lacunae, cavities within osteon lamellae (compact bone) or trabeculae (spongy bone). Lamellae are layers, endosteum lines cavities, and trabeculae are spongy structures—not residences. Answer is D, per the document.

Correct Answer: C

Rationale: The medullary canal (cavity) of long bones contains marrow (red in youth, yellow in adults). Trabeculae are in spongy bone, lamellae in compact, cells are in periosteum. Answer is C, per the document.

Correct Answer: D

Rationale: Compact bone has osteons (Haversian systems) with lamellae, osteocytes, and canaliculi, but no trabeculae (spongy bone feature). Answer is D, per the document.

Correct Answer: D

Rationale: Cancellous (spongy) bone has trabeculae (beams) and lamellae with osteocytes, but no osteons (compact bone feature). Answer is D, per the document.

Correct Answer: B

Rationale: Manubrium (top) and xiphoid process (bottom) are parts of the sternum (breastbone), not jaw, pelvis, or hand. Answer is B, per the document.