A. Muscle tissue: Muscle tissue is composed of cells (fibers) that have the unique ability to shorten or contract. This contraction generates the force required for body movement (skeletal muscle), pumping blood (cardiac muscle), and moving substances through hollow organs (smooth muscle). B. Connective tissue: The primary function of connective tissue is to support, bind together, and protect tissues and organs (e.g., bone, cartilage, blood, and adipose tissue). It provides structure but does not generate active movement through contraction. C. Epithelial tissue: Epithelial tissue forms the covering of all body surfaces, lines body cavities and hollow organs, and is the major tissue in glands. Its main functions are protection, secretion, absorption, and excretion. D. Nervous tissue: Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities by transmitting electrical signals (impulses), not by physical contraction.