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: Ophthalmology
Which of these can cause 3
rd
 nerve paralysis -a) Posterior communicating artery (PCA) aneurysmb) Tolosa - Hunt syndromec) Midbrain infarctd) Pons Infarcte) Lateral medullary lesion 
Select and explain. 
A. abc, B. bc, C. acd, D. bcd
A: abc
Answer: A: abc 
Explanation: Causes of occulornotor nerve paralysis

Infarct, haemorrhage, demyelination, infection, tumor.
Aneurysm ofposterior communicating artery & basilar artery.
Aneurysm, infarct, compression, tumor, meningitis.
Internal carotid artery aneurysm, carotid-cavernous fistula, cavernous sinus thrombosis, tumors (pituitary adenoma, meningioma, metastasis), herpes zoster, Tolosa-hunt syndrome.
Infarction of nerve e.g. diabetes, giant cell arteritis.