A 6-year-old boy who has mental retardation secondary to fragile X syndrome has been admitted to ...

A 6-year-old boy who has mental retardation secondary to fragile X syndrome has been admitted to hospital with a mitral valve prolapse.
 
  A health care worker who is providing care for the family should have which of the following statements as part of her knowledge base around the disease?
  A)
  The common pattern of inheritance is an affected mother who carries one normal and one mutant allele.
  B)
  The boy's mother had a 100 chance of transmitting the defective gene to her son.
  C)
  Genes of the boy's Y chromosome can be affected in addition to the X chromosome.
  D)
  The boy will pass the gene to all his future daughters who will become carriers.