Different Versions of the Protein Hemoglobin Are Found in a Baby's

Multiple Choice

Different versions of the protein hemoglobin are found in a baby's blood cells at different stages of development. Changes in the hemoglobin type present are most likely the result of

A) what genes are transcribed.
B) whether or not the transcribed mRNA can leave the nucleus.
C) how translated RNA is cut up.
D) how mRNA is distributed in the red blood cells.