Use the following pedigree (Figure 14.3) for a family in which dark-shaded symbols represent individuals with one of the two major types of colon cancer. Numbers under the symbols are the individual's age at the time of diagnosis.

Figure 14.3
-The affected woman in generation IV is thinking about her future and asks her oncologist (cancer specialist)whether she can know whether any or all of her children will have a high risk of the same cancer. The doctor would be expected to advise which of the following?
I.genetic counseling
II.prenatal diagnosis when/if she becomes pregnant
III.testing to see whether she has the allele
IV.testing to see whether her future spouse or partner has the allele