Pedigree Analysis Problem Solving

Study the pedigree chart given below:

What does it show?

1.	Inheritance of a sex-linked inborn error of metabolism
2.	Inheritance of a condition like phenylketonuria as an autosomal recessive trait
3.	The pedigree chart is wrong as this is not possible
4.	Inheritance of a recessive sex-linked disease like haemophilia

With the help of the given pedigree, find out the probability for the birth of a child having no disease and being a carrier (has the disease mutation in one allele of the gene) in generation.

1. 1/8
2. Zero
3. 1/4
4. 1/2