Final answer:
The genetic code of an organism is best identified by d) the sequence of bases in its DNA.
Step-by-step explanation:
The genetic code of an organism is best identified by the sequence of bases in its DNA. The DNA sequence is responsible for encoding the information that determines an organism's traits and characteristics. It is a unique sequence of nucleotide bases (adenine, cytosine, guanine, and thymine) that make up the genetic code.