This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ocular Embryology& Anatomy, Subject name: Ophthalmology
The Arrow points towards 
Select and explain. 
A. Superior Rectus, B. Trochlea, C. Inferior Rectus, D. Annulus of Zinn
B: Trochlea
Answer: B: Trochlea 
Explanation: The structure marked is the trochlea and the muscle is superior oblique