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: Surgery
Which of the following is the most common swelling of eyelids? 
Select and explain. 
A. Chalazion, B. Neurofibromatosis, C. Rodent ulcer, D. Dermoid cyst
A: Chalazion
Answer: A: Chalazion 
Explanation: These are the most common lid swellings. A meibomian cyst is a chronic granulomatous inﬂammation  of a meibomian gland. It may occur on either upper or lower lids and presents as a smooth, painless  swelling. It can be felt by rolling the cyst on the tarsal plate.
Key Concept:
Meibomian cyst: They are epidermal cysts found on the free  edge  of  eyelid.  
Chronic Meibomian cyst is called chalazion.