This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of Cornea, Subject name: Ophthalmology
Patient came to the OPD with recent onset photphobia within 24 hours and sloughing corneal ulcer. There is greenish ulcer base. Which of the following can be the causative organism: 
Select and explain. 
A. Acanthamoeba, B. Nocardia, C. Pseudomonas, D. Herpes
C: Pseudomonas
Answer: C: Pseudomonas 
Explanation: Pseudomonas Ulcer Rapid onset & Greenish ulcer base Produce biofilm that cause resistance MC cause of infection in contact lens users Nocardia ulcer resembles fungal ulcer in its characteristics.