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
Paralysis of 3rd, 4th, 6th, nerves with involvement of ophthalmic division of 5th nerve, localizes the lesion to - 
Select and explain. 
A. Cavernous sinus, B. Apex of orbit, C. Brainstem, D. Base of skull
A: Cavernous sinus
Answer: A: Cavernous sinus 
Explanation: Cavernous sinus lesions may be associated with paralysis of 3rd, 4th, 5th (ophthalmic and maxillary divisions) and 6th nerve on account of its characteristic relations.