The label that best matches osteocyte is c mature bone cell.
Osteocytes are the most abundant cells in mature bone tissue. They originate from osteoblasts, which are responsible for bone formation. Once osteoblasts become encased in the bone matrix they secrete, they transform into osteocytes. These cells play a crucial role in maintaining bone homeostasis and communicating with other bone cells, but they do not have the properties of stem cells (option a), do not dissolve the matrix (option b), nor do they primarily focus on secreting organic matrix (option d). Therefore, the correct label for osteocyte is ‘mature bone cell’.