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: Dental
The red zones of lips have: 
Select and explain. 
A. 30% sebaceous glands, B. 75% sebaceous glands, C. very small number of sebaceous glands, if any, D. absolutely no sebaceous glands
C: very small number of sebaceous glands, if any
Answer: C: very small number of sebaceous glands, if any 
Explanation: None