Narrative: Achondroplasia, a Hereditary Form of Dwarfism, Is an Autosomal Dominant

Multiple Choice

Narrative:
Achondroplasia, a hereditary form of dwarfism, is an autosomal dominant disorder; however homozygous dominant individuals either die before birth or very shortly thereafter. The homozygous recessive condition is normal. A dwarf couple decide to have children. Use this information to answer the following question:
Of the children of this couple who survive, what is the probability that they will be normal?

A) 0
B) ¼
C) 1/3
D) 2/3
E) ½