What is the most obvious expected finding when analyzing a four-generation pedigree for sex-linked dominant transmission of a trait?

Question

Quizplus · Accepted Answer

In sex-linked dominant transmission, the trait is always transmitted from an affected male to all his daughters, who are obligatory carriers, and then to half of his sons, but never from a father to his son. This is due to the fact that males only inherit one copy of the X chromosome from their mother, while females inherit two. Therefore, if the trait is on the X chromosome, a son can only inherit it from his mother who is a carrier, but not from his father who only passes on his Y chromosome.

What Is the Most Obvious Expected Finding When Analyzing a Four-Generation