This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mutations & Codons, Subject name: Biochemistry
Sta codon is: 
Select and explain. 
A. UAA, B. UAG, C. UGA, D. AUG
D: AUG
Answer: D: AUG 
Explanation: AUG : Sta Codon - Methionine First Amino acids in protein: Methionine (Eukaryotes) Formyl Methionine (Prokaryotes) Other three are stop codons: UAA, UAG, UGA