Could it be Birth control?
A) Due to the joining of the two gametes (sperm cell and egg which both have 23 chromosomes, the fertilised egg has 46 chromosomes) and because a skin cell is a normal cell (not a sex cell) it has 46 chromosomes.
You can automatically eliminate choice B because a zygote is the name for the cell produced when a sperm cell and egg joins, meaning it now has both 23 chromosomes from each of the sex cells, meaning it has 46 chromosomes. Sperm cells only ever have 23 chromosomes.
Using protection like condoms and getting tested regularly
The answer would be the third choice, <u>a study printed by the American Health Association.
</u><u />Hope this helps :)<u>
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