Match the pedigree to the correct type of inheritance.

Pedigree 1  -   Autosomal recessive

Pedigree 2  - Sex-linked recessive

Pedigree 3-  Sex- linked dominant

Pedigree 4-  Autosomal Dominant.

Explanation:

Pedigree 1 shows  Autosomal recessive inheritance because: (refer attachment)

Disease is not present in parents and only in one childParents are heterozygous  for autosomal trait. hence their genotype is Aa.Absence of trait in heterozygous individual shows that it is a recessive trait.

Pedigree 2 shows Sex- linked recessive disorder because:

The disease appears almost always in males.in the second generation the daughter is effected but her husband is not.But again their daughters are unaffected while all sons are affected.

Pedigree 3 shows Sex link dominant inheritance because:

Affected female transmitted the disease to her son.Effected father has all effected daughter.

Pedigree 4 shows Autosomal dominant inheritance because:

Each affected individual has an affected parents.Since both parents have the disease and their daughter does not  this shows that the parents are heterozygous for the trait and the trait is Dominant.

[ Refer to  the attatchment ]