The shaft of a long bone is the:

Correct Answer: B

Rationale: The diaphysis is the long, cylindrical shaft of a long bone, primarily compact bone, providing strength. The epiphysis is the end, the endosteum lines the interior, and the periosteum (misspelled here as 'periosteium') is the outer membrane, making 'diaphysis' the correct answer.

Correct Answer: C

Rationale: Intramembranous ossification forms bone directly from fibrous connective tissue membranes, as in flat skull bones. Hematopoiesis makes blood cells, endochondral ossification uses cartilage, and remodeling reshapes bone, making 'intramembranous ossification' correct.

Correct Answer: D

Rationale: The appendicular skeleton includes limbs and girdles. The coxal bone (hip) is part of the pelvic girdle, thus appendicular. Cranium, ribs, and sternum are axial skeleton components, making 'coxal bone' correct.

Correct Answer: C

Rationale: The sphenoid bone, butterfly-shaped, forms the cranium’s floor and sides, housing the pituitary. The ethmoid is anterior, occipital posterior, and temporal lateral, making 'sphenoid' correct.

Correct Answer: B

Rationale: The mandible (lower jaw) is the only skull bone that moves, via the temporomandibular joint, enabling chewing. The cranium, maxilla, and vomer are fixed, making 'mandible' correct.