Step 1: What the question asks.
In the Human Genome Project, we want the name of the method that maps the whole genome, both coding and non-coding parts.
Step 2: Meaning of annotation.
Once the DNA sequence is read, scientists go through it and label what each region is, where the genes are, where the regulatory and non-coding stretches lie. This labelling of the full set is called sequence annotation.
Step 3: Why ESTs do not fit.
Expressed sequence tags only look at genes that are actually transcribed (the coding, expressed regions). They skip the non-coding parts, so they cannot map the whole genome.
Step 4: Why the other options do not fit.
Single nucleotide polymorphism is about single-base differences between people. Electrophoresis is just a lab technique to separate DNA fragments by size. Neither names the whole-genome mapping approach.
Step 5: Conclusion.
Therefore the correct answer is "Sequence Annotation". \[ \boxed{\text{Sequence Annotation}} \]