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
Preimplantataion genetic diagnosis is used for 
Select and explain. 
A. Fetal gender determination, B. Single gene mutation analysis, C. HLA typing, D. Karyotyping
B: Single gene mutation analysis
Answer: B: Single gene mutation analysis 
Explanation: Pre implantation genetic diagnosis is used for daignosis of single gene disorders such as cystic fibrosis, β - thalassemia and hemophilia.