The karyotype indicates a problem with chromosome 18. What is the problem and what is the BEST explanation for why it occurred?
Aextra chromosome; insertion
Bforeign chromosome; deletion
Cextra chromosome; nondisjunction
Dmutated chromosome; crossing over
Aextra chromosome; insertion
Bforeign chromosome; deletion
Cextra chromosome; nondisjunction
Dmutated chromosome; crossing over