Haemophilia is more commonly seen in human males than in human females because

Options

A. this disease is due to an X-linked dominant mutation
B. a greater proportion of girls die in infancy
C. this disease is due to an X-linked recessive mutation
D. this disease is due to a Y-linked recessive mutation

Answer

C

Explanation

Haemophilia, hereditary (recessive X-linked) disease is caused due to fault in genes controlling the factor VIII and IX, located on X-chromosome. The male carries only one X-chromosome, other sex chromosome carries no genes for blood clotting, so the condition is usually seen only in males where only one faulty chromosome is needed.
While a female with one faulty X-chromosome will be carrier. So, in females two faulty X-chromosomes are needed to cause the disease.