How is the sex of a newborn in humans determined?

(N/A) The sex of an individual is genetically determined. Humans have $23$ pairs of chromosomes. Out of these,$22$ pairs are autosomes,and the $23$rd pair consists of sex chromosomes.
Females have two $X$ chromosomes $(XX)$,while males have one $X$ and one $Y$ chromosome $(XY)$.
During fertilization,the mother always contributes an $X$ chromosome to the zygote.
The sex of the child depends on the chromosome contributed by the father:
$1$. If the father contributes an $X$ chromosome,the zygote becomes $XX$,resulting in a girl.
$2$. If the father contributes a $Y$ chromosome,the zygote becomes $XY$,resulting in a boy.