Final answer:
The spicules of spongy bone unite to form trabeculae, which are surrounded by the endosteum. The correct answer is C. Endosteum.
Step-by-step explanation:
In bone anatomy, spicules are small, needle-like structures that form the trabeculae of spongy bone. Trabeculae are interconnected plates or struts that provide strength to spongy bone, also known as cancellous or trabecular bone.
The trabeculae are surrounded by the endosteum, which is a delicate membranous lining found on the inner surface of bone. It is responsible for bone growth, repair, and remodeling. It also helps in exchanging nutrients and waste products with the bone marrow in the medullary cavity. Therefore, The correct answer is C. Endosteum.
This question is not complete, Here I am attaching the complete question:
Spicules unite to form trabeculae of spongy bone surrounded by endosteum:
A. Periosteum
B. Epiphysis
C. Endosteum
D. Medullary cavity