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
Familial dysautonomia is characterised by absence of: 
Select and explain. 
A. Fungiform papilla, B. Circumvallate papilla, C. Filiform papilla, D. Both 1 and 2
D: Both 1 and 2
Answer: D: Both 1 and 2 
Explanation: Familial dysautonomia is characterised by absence of both fungiform and circumvallate papilla.