Correct Answer: D
Explanation:
There are two forms of cells in cartilage: chondroblasts and chondrocytes. The chondroblasts are cells that secrete the major component of the cartilage, i.e. the extracellular matrix (ECM). Some chondroblasts may be entrapped inside the ECM that they secrete. When that happens they become less active in producing ECM, and turn into chrondocytes that function mainly in the diffusion of nutrients and other substances and the repair of the matrix.