Answer:
Alleles are passed from the parents' sex chromosomes to the sex chromosomes in the offspring.
Step-by-step explanation:
Sex-linked traits are simply traits that are associated, or found with, a particular sex chromosome (so X or Y). The way that alleles are passed down is through fertilization, but before that, the actual gametes (sex cells) involved in fertilization have to be synthesized. And because a sex linked trait is linked with a particular sex chromosome, that trait gets put into a gamete with that sex chromosome and is in turn passed down to the sex chromosomes of the offspring.