Four stages in protein production are shown below. 1. An mRNA copy of the gene is made. 2. The mRNA moves into the cytoplasm. 3. The mRNA attaches to a ribosome. 4. The ribosome joins amino acids together to form a protein molecule. In what order do these events usually take place?
- A$1 \rightarrow 2 \rightarrow 3 \rightarrow 4$
- B$2 \rightarrow 1 \rightarrow 3 \rightarrow 4$
- C$4 \rightarrow 2 \rightarrow 1 \rightarrow 3$
- D$4 \rightarrow 3 \rightarrow 2 \rightarrow 1$