Which of the following is not a property of the blood-brain barrier?

A) The capillary endothelial cells are interconnected by tight junctions.
B) It is very permeable to many water and lipid-soluble compounds.
C) Astrocytes surround the CNS capillaries.
D) It is absent in portions of the hypothalamus.
E) It is intact except in areas known as circumventricular organs.