Which of the following diseases is known as a 'bleeder's disease',caused by the presence of an $X$-linked recessive gene?

$A$ normal woman whose father was colourblind marries a normal man. What kinds of children would be expected and in what proportion?

Study the pedigree chart of a certain family given below and select the correct conclusion which can be drawn for the character.

Of a normal couple,half the sons are haemophilic while half the daughters are carriers. The gene is located on $:-$

$A$ normal-sighted man, whose father was color-blind, marries a woman whose father was also color-blind. They have their first child as a daughter. What is the probability that this child will be color-blind (in $\%$)?

Knowing that albinism is determined by a recessive gene in humans,the presence of albinism in children born to a couple proves that: