Final answer:
The element not seen during an acute inflammatory response is reduced leukocyte migration, as inflammation actually involves leukocytes migrating to the site of infection to combat pathogens.
Step-by-step explanation:
Which of the following is NOT seen at infected sites as a consequence of an acute inflammatory response? The options are a) Vasodilation, b) Increased vascular permeability, c) Enhanced blood flow, and d) Reduced leukocyte migration. The correct answer is d) Reduced leukocyte migration. In the process of inflammation, chemicals such as cytokines and histamines are released, leading to vasodilation, increased vascular permeability, and thereby, enhanced blood flow. These events facilitate the movement of leukocytes to the site of infection, not the reduction of it. Leukocytes play a crucial role by migrating to the site, where they phagocytize pathogens and help in resolving the inflammation.