A married couple has four girl children but no boys. This
does not mean that the husband produces only X sperms.
Explain why not.

Explanation:

All children have 'chromosomes' whether the child is girl or boy. Women have XX, Men have XY. Children inherit one piece from each parent. A baby can only receive an X from their mother because their mother only has X. If the baby gets an X from their father, they will have XX and be a girl. If they inherit their fathers Y, they will have XY and be a boy.

So since the Y only can come from their father, this method of inheritance relies on the ability of the father to deliver Y genetic material. A man has two types of sperm. Sperm that is predominantly X carrying and sperm that is predominantly Y. There is a gene(s) that control what sort he produces.

It doesn't mean he doesn't have Y bearing sperm. It just means he may be genetically predisposed to X bearing sperm.

a chain link fence because there so tiny even my albino donkey can't get out

only about ten percent of the energy at one trophic level is passed on to organisms at the next trophic level. the remainder of the energy is used in life processes or lost as heat.