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 cranial nerve with the longest intracranial course? 
Select and explain. 
A. Optic, B. Abducent, C. Trigemina, D. D i.e., Trochlear
D: D i.e., Trochlear
Answer: D: D i.e., Trochlear 
Explanation: D i.e., Trochlear