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
A soft contact lens users have corneal keratitis cause is – 
Select and explain. 
A. Acanthamoeba – ulcer, B. Erosion of cornea, C. Pseudomonas infection, D. Herpes infection
C: Pseudomonas infection
Answer: C: Pseudomonas infection 
Explanation: "Pseudomonas aeruginosa is the most common organism encountered in contact lens-related acute keratitis and corneal ulcer".
-Holland & Mannis
Acanthamoeba is the 2nd most common cause.