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: Biochemistry
Amber codon is: 
Select and explain. 
A. UAA, B. UAG, C. UGA, D. UAC
B: UAG
Answer: B: UAG 
Explanation: Terminator Codons/Stop Codons/Nonsense Codons
UAG --- Amber
UGA --- Opal
UAA --- Ochre
Exceptions
UGA can be recoded to Selenocysteine.
UAG can be recoded to Pyrrolysine.
UGA codes for Tryptophan in mitochondrial DNA.
Reference- Harper 30th edition Pg- 415