I believe it is the nucleus.
The RNA codon will be GAU, pairing Cytosine-Thymine-Adenine DNA codon with Guanine-Adenine-Uracil RNA codon. This codon is the Amino Acid, Aspartic Acid. In this codon we see Uracil which is the counterpart of Thymine in the RNA.
B .How organisms could change .
Answer:
Plant Growth increases in the spring
C. The gravity of the moon