This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
The arachnoid villi responsible for cerebrospinal fluid absorption protrude mainly in the - 
Select and explain. 
A. Superior sagittal sinus, B. Inferior sagittal sinus, C. Straight sinus, D. Transverse sinus
A: Superior sagittal sinus
Answer: A: Superior sagittal sinus 
Explanation: The main site of absorption is through arachnoid villi and arachnoid granulations into subdural venous sinuses. These arachnoid villi and granulations are most numerous in superior sagital sinus and its lateral lacunae.