Final answer:
The tissue in question is bone, or osseous tissue. It is a dense connective tissue that forms the skeleton, providing support, protection, and a framework for the body.
Step-by-step explanation:
The rigid connective tissue that provides support, frameworks, and attachments, protects underlying tissues, and forms structural models for many developing bones is bone, or osseous tissue. Bone is a hard, dense connective tissue that forms the adult skeleton, comprising the support structure of the body. Alongside bone, the skeletal system includes cartilage, which is a type of dense connective tissue offering a smooth surface for bone movement at joints, and ligaments, which are bands of fibrous connective tissue holding bones together at joints.
Bone tissue is unique because its rigid extracellular matrix contains mostly collagen fibers embedded in mineralized ground substance with hydroxyapatite, essentially calcium phosphate. This combination provides a balance of flexibility, due to the collagen, and strength, due to the mineral content, thus preventing bones from being overly brittle or overly flexible. The skeletal system plays a critical role in movement, support, and protection of vital organs.