Final answer:
Connective tissue is made up of cells, ground substance, and protein fibers.
Step-by-step explanation:
Connective tissue is made up of a matrix consisting of living cells and a non-living substance called the ground substance. The ground substance is made up of an organic substance (usually a protein) and an inorganic substance (usually a mineral or water). The principal cell of connective tissues is the fibroblast, which makes the fibers found in nearly all connective tissues. Therefore, the answer is b. cells, ground substance, and protein fibers.