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
Ophthalmic examination of a patient shows 'Herbe pits' on cornea which is characteristic of the following infection: 
Select and explain. 
A. Trachoma, B. Psoriasis, C. Spring catarrh, D. Fungal keratitis
A: Trachoma
Answer: A: Trachoma 
Explanation: In established trachoma (caused by caused by C trachomatis serovars A, B, Ba, or C), there may also be superior epithelial keratitis, subepithelial keratitis, pannus, or superior limbal follicles, and ultimately the pathognomonic cicatricial remains of these follicles, known as Herbe's pits--small depressions covered by epithelium at the limbocorneal junction. Ref: Nijm L.M., Garcia-Ferrer F.J., Schwab I.R., Augsburger J.J., Correa Z.M. (2011). Chapter 5. Conjunctiva & Tears. In P. Riordan-Eva, E.T. Cunningham, Jr. (Eds), Vaughan & Asbury's General Ophthalmology, 18e.