Which type of tissue is primarily responsible for forming the structure of organs?

Connective tissue is primarily responsible for forming the structure of organs because it provides support, elasticity, and the framework necessary to hold different tissues and organs together. It consists of a variety of cell types and an extracellular matrix, which can include fibers and ground substance, contributing to the overall structure and function of organs. Connective tissue also plays a pivotal role in transporting nutrients and waste products, storing energy, and insulating body structures.

In contrast, epithelial tissue primarily serves as a protective layer, covering surfaces and lining cavities but does not form the structural framework of organs. Muscular tissue is specialized for movement and is not inherently involved in forming the organ's foundational structure. Nervous tissue is responsible for transmitting impulses and processing information, rather than providing structural support to organs. Thus, connective tissue is the most accurate choice for the type of tissue primarily responsible for forming the structure of organs.