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
Topical azelaic acid is used in – 
Select and explain. 
A. Hyperpigmentary disorders, B. Dermatophyte infections, C. Vitiligo, D. Mixed infections
A: Hyperpigmentary disorders
Answer: A: Hyperpigmentary disorders 
Explanation: Azelaic acid is a depigmenting agent. Other depigmenting agents are hydroquinone, retinoic acid, kozic acid, glycolic acid, monobenzyl ether of hydroquinone.