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: Anaesthesia
The pulse oximetry reading is affected in 
Select and explain. 
A. Anemia, B. Jaundice, C. Red nail polish, D. Dark skin
D: Dark skin
Answer: D: Dark skin 
Explanation: Pulse oximetry values can be erroneous in dark skin. But in all other cases it is normal.