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
Deficiency of enzyme hexosaminidase, n subunit causes - 
Select and explain. 
A. Tay-Sachs disease, B. Hurler syndrome, C. Fabry disease, D. Pompe disease
A: Tay-Sachs disease
Answer: A: Tay-Sachs disease 
Explanation: Ans. is 'a' i.e., Tay- Sach's disease