The following pedigree diagram shows the inheritance of a rare genetic disorder in a family (filled shapes depict affected individuals). Which one of the following is the most likely pattern of inheritance of the disorder?

Step-by-step solution

Based on the pedigree diagram, we can determine the mode of inheritance by analyzing the transmission of the trait: 1. Generation I: An affected male and an unaffected female have offspring where all daughters are affected and all sons are unaffected. This is a classic hallmark of an X-linked dominant trait. The affected father ( X^D Y ) passes his affected X chromosome to all his daughters (making them X^D X^d , affected) and his Y chromosome to all his sons (making them X^d Y , unaffected). 2. Generation III: We