Which protein is most directly responsible for providing tensile strength to skin, tendons, and bone matrix?

• A. Hemoglobin, which is a transport protein that has no direct structural role in connective tissue
• B. Myosin, a motor protein that primarily generates sliding motion between filaments rather than providing extracellular tensile strength
• C. Amylase, an enzyme that digests starch and is unrelated to connective tissue structure
• D. Collagen, the major fibrous structural protein that forms cross-linked fibers providing tensile strength to connective tissues

Answer: (D)