Which describes the genes on each pair of chromosomes?

a.The alleles must be the same; the genes are in a different order.
b.The alleles can be different; the genes are in a different order.
c.The alleles can be different; the genes are in the same order.
d.The alleles must be the same; the genes are in the same order.

d. The alleles must be the same; the genes are in the same order.