Males and Females Express the Same Amount of X-Chromosome Genes

Males and females express the same amount of X-chromosome genes despite the fact that females have more X chromosomes.Animals approach this problem in different ways.Which of the following is an example?

A) Female Caenorhabditis elegans express X-chromosome genes at 50%.
B) Male fruit flies double the expression of their X-chromosome genes.
C) Female humans inactivate one of their X chromosomes.
D) all of the above
E) none of the above