Sally,age 28,recently Married John,age 45

Multiple Choice

Sally,age 28,recently married John,age 45.They would like to have a child,but they are concerned that they may be at high risk to have a child with a chromosomal abnormality,like Down's syndrome,because of John's age.What is their genetic counselor likely to tell them?

A) They are at higher than average risk for some chromosomal disorders because of John's age,but not for Down's syndrome.
B) They are at higher than average risk for chromosomal disorders of all sorts because of John's age.
C) There is no relationship between parents' age and chromosomal disorders in their offspring.
D) The risk of any chromosomal disorder in a child is only related to the mother's age,not to the father's age.