Why are males more likely to express a sex-linked trait than females? A. They inherit the sex-linked trait from both parents. B. Females do not carry sex-linked traits in their chromosomes. C. Males contain one X allele which they inherit from the mother and females have another X chromosome to cover the affected allele. D. Females only need one recessive gene to express the trait.

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods.c. it shows that these organisms share the same habitat.d. it provides evidence that these organisms suffered a genetic mutation.