Final answer:
The expansion of CCG trinucleotide repeats on chromosome 11 is associated with Fragile X syndrome, not Huntington's disease, myotonic dystrophy, or Friedreich's ataxia.The correct answer is option A.
Step-by-step explanation:
The expansion of CCG trinucleotide repeats on chromosome 11 is associated with Fragile X syndrome. Myotonic dystrophy is characterized by the expansion of the CTG trinucleotide repeat but it affects chromosome 19. Huntington's disease involves an expansion of CAG trinucleotide repeats on chromosome 4, and Friedreich's ataxia is associated with GAA repeats on chromosome 9.
The expansion of trinucleotide repeats in these diseases causes them to be categorized as trinucleotide repeat disorders, a group of genetic disorders caused by trinucleotide repeat expansion within genes.The correct answer is option A.