Considering that males can have Klinefelter ( XXY) syndrome, xYY and normal xY chromosomal combinations, and females can have Turner ( X0 ) syndrome, poly-X (XXX, XXXX), and normal xx combinations, it is obvious that

a. Male characteristics result from the presence of only one x chromosome.
b. Sex determination is a delicate balance between x and Y chromosomes.
c. Female characteristics result from the presence of two or more x chromosomes.
d. Male characteristics result from the minimal presence of one Y chromosome.
e. Male characteristics result from the absence of two or more x chromosomes.