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: Skin
Acanthosis nigricans is associated with malignancies and: March 2013 
Select and explain. 
A. Hypeension, B. MI, C. Insulin resistance, D. Leprosy
C: Insulin resistance
Answer: C: Insulin resistance 
Explanation: Ans. C i.e. Insulin resistance Acanthosis nigricans Characteristic of acanthosis nigricans: - Dark, - Thick, - Velvetty skin (in body folds and creases) MC cause of acanthosis nigricans: Type 2 DM Internal malignancies associated with acanthosis nigricans: - Adenocarcinoma lungs, - Carcinoma GIT etc.