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
Surgery indicated for ptosis in Horner's syndrome 
Select and explain. 
A. Fasanella - servat, B. Levator resection, C. Blaskovics operation, D. Frontalis sling
A: Fasanella - servat
Answer: A: Fasanella - servat 
Explanation: Fasanella - servat indications:

Mild ptosis with good levator action.
Horner's syndrome.