Final answer:
The extracellular matrix of alveolar bone is composed of approximately 70% inorganic material, which provides the bone with its strength and rigidity.
Step-by-step explanation:
The extracellular matrix of alveolar bone predominantly consists of inorganic material. The inorganic matrix is mainly composed of mineral salts, with the majority being calcium salts. This inorganic component provides the hardness and rigidity necessary for the structural support of alveolar bone. The correct answer to the question 'Extracellular matrix of alveolar bone consists of what % of inorganic material?' is c. 70%.