Which of the Following Statements Supports the Proposition That the Presence

Which of the following statements supports the proposition that the presence of an X chromosome appears to be necessary for life?

A) X-chromosomal genotypes are expressed as consistent phenotypes at a rate of around 85%, while Y-chromosomal genotypes are expressed as consistent phenotypes at a rate of only about 15%.
B) The X chromosomes are expressed far earlier in the prenatal period than the Y chromosomes.
C) There are no chromosomal disorders wherein a person has only Y chromosomes.
D) Most of the lethal chromosomal disorders, including Tay-Sachs disease and cystic fibrosis, are located on the Y chromosome.