Webbed fingers is inherited as a recessive X-linked trait. An unaffected male has children with an affected female. What is the chance that their male children will have webbed fingers? A. 50% of their male children will have the trait.
B. 100% of their male children will have webbed fingers
C. 0% of their male children will have webbed fingers.
D. 25% of their male children will have the trait

NOTE : I know that the answer is not A. 50% of their male children will have the trait.