The correct answer is: about 99%.
The main difference between two random people’s genetic make-up issingle base pair differences, or polymorphisms (SNPs). There are about one SNP per 1000 bases. Since the human genome is about 3 Gbp long, about 3 million SNPs among two random people is present. SNPs may occur within coding sequences of genes, non-coding regions of genes, or in the intergenic regions.