This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Microbiology
Length of intraorbital pa of the optic nerve is 
Select and explain. 
A. 10-12 mm, B. 20-24 mm, C. 25-30 mm, D. 35-40 mm
C: 25-30 mm
Answer: C: 25-30 mm 
Explanation: Length of optic nerve - 5 cm Intraocular poion - 20 mm Intraorbital poion - 30 mm