How does inflammation occur in the body?

Inflammation is a complex biological response that occurs when tissues are injured or affected by pathogens, and it serves as a protective mechanism aimed at healing and restoring homeostasis. The correct choice identifies that when tissue is damaged, immune cells indeed release histamines. Histamines play a critical role in the inflammatory process by causing blood vessels to dilate (expand) and become more permeable, allowing immune cells to access the site of injury or infection. This response leads to the classic signs of inflammation, including redness, heat, swelling, and pain.

The release of histamines and other chemical mediators is essential because it helps the body to recruit additional immune cells to fight off infection and to initiate the healing process. Such an increase in blood flow and the arrival of immune cells are vital for addressing the tissue damage and restoring normal function.

In contrast, while the other options might relate to different physiological processes, they do not accurately describe the initiation of inflammation. For instance, blood vessel constriction reduces blood flow and is not conducive to the inflammatory response, which relies on increased blood flow. Excess hormones or nutrient depletion may influence the body's overall health, but they are not primary drivers of the inflammatory process itself.