Answer:
X inactivation
Step-by-step explanation:
The female mammals have double the number of X-linked genes as compared to their counterpart males. During early embryonic development, either the maternal or paternal X chromosome in all the cells of a female is inactivated by the process of heterochromatinization. The inactivated X chromosome is present in the form of a Barr body. This inactivation of the X chromosome is a random event.
The inactivated X chromosome of a cell remains in the same state in all of its progeny cells. In this way, the process of X inactivation balances the dosages of X-linked genes between males and females.