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: Gynaecology & Obstetrics
Which one of the following test detects Fetal skin cells? 
Select and explain. 
A. Shake test, B. Nile blue sulphate test, C. Litmus test, D. All of the above
B: Nile blue sulphate test
Answer: B: Nile blue sulphate test 
Explanation: Nile blue sulphate test