Which one of the following statements about segregation of the sex chromosomes is FALSE?

a. The secondary sex ratio of males to females at birth usually shows a slight excess of males
b. In humans, half of the fertilized eggs are expected to be male and half are expected to be female; this 1:1 ratio is characteristic of Mendelian segregation
c. In humans, the sex at each birth is not a random process because there are often large families with either all girls or all boys
d. In human males, segregation of the x chromosome from the Y chromosome occurs during anaphase 1 of meiosis.