This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of sebaceous and sweat glands, Subject name: Dental
Example of sebaceous glands opening directly to the surface of the skin, and not by way of a hair follicle are all except 
Select and explain. 
A. Meibomian glands of the eyelids, B. Tyson's glands of the prepuce, C. Koplik's spots, D. Fordyce's spots
C: Koplik's spots
Answer: C: Koplik's spots 
Explanation: In a number of sites, sebaceous glands open directly to the surface of the skin, and not by way of a hair follicle. Examples of such glands are the Meibomian glands of the eyelids and the Tyson's glands of the prepuce. Free sebaceous glands are also found on the mucocutaneous surfaces of the female genitalia, areola, and ectopic sites like tongue and cervix Free sebaceous glands in the margin of the upper lip are often visible to the naked eye as pale-yellow bodies, which vary in size from minute specks to about 1.5 mm in diameter; they are known as Fordyce's spots. Koplik's spots are pathognomonic for measles seen as 1- to 2-mm white or bluish lesions with an erythematous halo on the buccal mucosa near the upper 1st and 2nd molars