In the following human pedigree, the filled symbols represent the affected individuals. Identify the type of given pedigree:
1. Autosomal dominant
2. X-linked recessive
3. Autosomal recessive
4. X-linked dominant
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 |