This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
Poly (A) tail translates into 
Select and explain. 
A. Polyproline, B. Polylysine, C. Polyalanine, D. Polyglycine
B: Polylysine
Answer: B: Polylysine 
Explanation: A poly (A) tail is added to the 3&; end of the pre-mRNA once elongation is complete. The poly (A) tail protects the mRNA from degradation, aids in the expo of the mature mRNA to the cytoplasm, and is involved in binding <a href=" involved in initiating translation.</li>