Which of the following structures is made up of cartilage and ligaments?

The trachea is indeed composed of cartilage and ligaments. Its structure is primarily supported by C-shaped rings of hyaline cartilage, which provide rigidity and keep the airway open, while the surrounding connective tissues contain ligaments that help maintain the structure of the trachea and allow for some flexibility. This combination of cartilaginous rings and ligaments is essential for the proper function of the respiratory system, as it enables the trachea to withstand changes in pressure and avoid collapse during inhalation and exhalation.

In contrast, the other options do not consist of a structure that is primarily made up of cartilage and ligaments. The bronchi, while also featuring cartilage, primarily consist of airway tissue that branches from the trachea. The lungs are composed of soft, spongy tissue made up mainly of alveoli and do not contain significant amounts of cartilage. The diaphragm is a muscle that plays a crucial role in respiration, but it is mainly made up of muscle fibers rather than cartilage or ligaments.