Final answer:
The central structure in the middle of a liver lobule is a central vein. Hepatocytes surround the hepatic sinusoids, which receive oxygen-rich and nutrient-rich blood. The option (C) is correct.
Step-by-step explanation:
The central structure in the middle of a liver lobule is a central vein. Hepatocytes, which are liver cells, surround the fenestrated endothelium of hepatic sinusoids, which are open blood spaces in the liver.
The liver lobules receive oxygen-rich blood from the hepatic artery and nutrient-rich blood from the hepatic portal vein. The processed blood then flows to the central vein and eventually to the inferior vena cava. The processed blood flows to the central vein and eventually to the inferior vena cava. Therefore, option (C) is correct.