Question

In females, both sex chromosomes are X chromosomes. Males have one X and one Y chromosome. Why are sex-linked traits more commonly expressed in males that in females?

A. All alleles on the X chromosome are dominant.
B. All alleles on the Y chromosome are recessive.
C. A recessive allele on the X chromosome will always produce the trait in a male.
D. Any allele on the U chromosome will be codominant with the matching allele on the X chromosome.

Answer 1

A recessive allele on the X chromosome will always produce the trait in a male

Answer 2

C. A recessive allele on the X chromosome will always produce the trait in a male

This is because males only have one X chromosome so if the trait is there in the DNA strand they will have it.