What is described as increased blood flow to a specific area of the body?

The correct choice is hyperemia, which refers to the increased blood flow to a specific area of the body. This condition can occur as a response to various stimuli, such as inflammation, injury, or increased metabolic activity in tissues. Hyperemia results in a reddish appearance of the affected area due to the engorgement of blood vessels with oxygen-rich blood.

In contrast, hypoxia refers to a deficiency of oxygen in the tissues, ischemia is a decrease in blood flow to an area, typically leading to tissue damage, and thrombosis is the formation of a blood clot within a blood vessel, which can obstruct blood flow. Understanding these terms is crucial in the context of vascular and tissue response, especially in clinical and anatomical studies.