Nettie Maria Stevens was the first scientist to describe the chromosomal basis of sex. In mammals, females have identical sex chromosomes called X, and males have an X chromosome and a smaller Y chromosome.

Hemophilia is characterized by the difficulty of individuals in clotting blood. The disease is determined by a gene (h) present on the differential segment of the X chromosome that is recessive to its normal allele (H). 
Observe the following family tree of the English royal family and answer what will be the genotype of:

 

a) Queen Victoria. 
b) Prince Albert. 
c) Alfonso XIII, King of Spain. 
d) Alfonso, Prince of Asturias. 
e) Juan Carlos I, king of Spain. 
f) Infanta Cristina 
g) Prince Felipe