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: Pathology
Talon's cusp is characteristic of which syndrome 
Select and explain. 
A. Edward's syndrome, B. Klinefelter's syndrome, C. Rubinstein -Taybi syndrome, D. Down's syndrome
C: Rubinstein -Taybi syndrome
Answer: C: Rubinstein -Taybi syndrome 
Explanation: None