Pick the incorrect statement with regard to haemophilia:

The correct option is B

It is a dominant disease

The correct option is B.

Explanation of the correct option:

1. Haemophilia is a sex-linked recessive disorder.
2. The gene for it is present on the X chromosome.
3. An unaffected carrier female passes it onto some of her male offspring.
4. Hence, it is not a dominant disorder.

Explanation of the incorrect options:

Option A:

This is correct concerning haemophilia as a single protein that is a part of a cascade of proteins involved in blood clotting is affected.

Option C:

This is correct about haemophilia as it is a recessive disease.

Option D:

This is correct concerning haemophilia as the gene for it is present on the X chromosome.

Final answer: The incorrect statement concerning haemophilia is it is a dominant disease.