This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics of Common Disorders, Subject name: Pediatrics
Turner syndrome - 
Select and explain. 
A. 45XO, B. 46XO, C. 47XXX, D. Trisomy 21
A: 45XO
Answer: A: 45XO 
Explanation: Ans. is 'a' i.e., 45XOTrisomy 13- Patau syndromeTrisomy 18- Edward syndromeTrisomy 21- Down syndromeXO- Turner syndromeXXY- Klinefelter syndrome