Help molecular biology question

A polypeptide with a length of 150 amino acids is found to be coded for by a cytoplasmic mRNA molecule of 1050 bases. The most likely explanation of this is

A.mRNA processing has not yet occurred
B.Some of the mRNA lies outside initiation and termination codons
C.Transcription was initiated at a point several hundred bases into the mRNA molecule
D.It is a result of degeneracy of the genetic code

is it A? can someone explain this to me

Reply 1

Jimbo1037629

I think that it is A. This is because after the formation of the mRNA during transcription, the mRNA consists of introns and exons, and the introns must be removed,decreasing the length of the mRNA strand. B cannot be correct as the initiation and termination strands also determine the point at which translation begins. mRNA cannot bind to a ribosome halfway along the molecule. C has the same explanation as B. D cannot be correct as the degeneracy of the genetic code refers to the fact that multiple RNA triplets can code for the same amino acid. This would still result in a 3 RNA nucleotide to 1 Amino acid ratio that is not present as shown in the question.