This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Brain , Subject name: Anatomy
Which area is out of the blood-brain barrier? 
Select and explain. 
A. Thalamus, B. Cerebral coex, C. 4th ventricle, D. Area postrema
D: Area postrema
Answer: D: Area postrema 
Explanation: Areas devoid of blood-brain barrier are Pineal gland,Posterior lobe of pituitary,Tuber cinerum Wall of supraoptic recess of third ventricle,Area postrema.These are the areas where the neuronal receptors sample the chemical contents of blood directly. (Ref: Vishram Singh textbook of clinical neuroanatomy, 2nd edition. Pg- 183)