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
All of the following are signs of mycotic corneal ulcer, EXCEPT: 
Select and explain. 
A. Big hypopyon, B. Sterile immune ring, C. Corneal vascularisation, D. Feathery finger like extensions into the stroma
C: Corneal vascularisation
Answer: C: Corneal vascularisation 
Explanation: Corneal vascularisation is conspicuously absent in a mycotic corneal ulcer. The salient features of a mycotic corneal ulcer are: Dry looking, greyish white with elevated rolled out margins Feathery finger like extensions into the surrounding stroma Presence of sterile immune ring Small satellite lesions around the ulcer Big hypopyon which may not be sterile Absent corneal vascularisation Ref: Ophthalmology By A. K. Khurana page 123.