Concept:Hemophilia is a genetic bleeding disorder caused by a recessive gene carried on the X chromosome.
Explanation:Hemophilia is inherited when a child receives a faulty gene from a parent.
This faulty gene is located on the X chromosome and behaves as a recessive gene.
A recessive gene only shows its effect when an individual has two copies of it, or in males who have only one X chromosome.
Because females have two X chromosomes, they can be carriers without showing the disorder.
Males are more likely to develop hemophilia because they have only one X chromosome.
Therefore, the trait is not controlled by blood group, a dominant gene, or the rhesus factor.
Answer:D. recessive gene