Alterations in Chromosome Number Can Occur with Any Chromosome, but Most

Alterations in chromosome number can occur with any chromosome, but most alterations are not seen in human populations because

A) the phenotype is homozygous recessive.
B) the phenotype is expressed in a continuous range in a given population and thus does not stand out.
C) they are lethal during fetal development.
D) most are corrected during the first mitotic event in the fertilized egg.
E) the genotype still represents a normal condition.