The venous system comprising of the hepatic portal vein and other veins. It is responsible for directing blood from the region of the gastrointestinal tract between the esophagus and rectum and also includes venous drainage from the supplementary organs such as the spleen to the liver. The hepatic system is so named since it connects capillaries of the intestine and other digestive organs to modified capillaries (hepatic sinusoids) of the liver. As intestinal blood is nutrient rich for few hours after having a meal, this system is able to detect available nutrients before the blood goes to rest of the body. It also plays the role in cleansing the blood by removing the bacteria and toxins present in it. Thus, the correct answer is option A.

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