Given below is a pedigree chart showing the inheritance of a certain sex-linked trait in humans

Key:

The trait traced in the above pedigree chart is

Options

A. dominant X-linked
B. recessive X-linked
C. dominant Y-linked
D. recessive Y-linked

Answer

A

Explanation

In the given chart the disease is inherited by female child from his father and none of the male child is affected hence it shows that the disease is X linked. Moreover, in the progeny the disease is expressed phenotypically by female child even if it is carrier, so the disease is dominant. Hence the pattern of disease is X linked dominant.