The correct option is C Huntington's Chorea
Huntington's disease is caused by an inherited defect in a single gene. Huntington's disease is an autosomal dominant disorder, which means that a person needs only one copy of the defective gene to develop the disorder.
While Cystic Fibrosis, Phenylketonuria, and Alzheimer's disease are autosomal recessive diseases.
The correct answer is "option A"