ANSWER:
d. Because women and children are given priority when evacuating a sinking ship, sometimes families are split apart during the crisis.
Option A is incorrect as the plural of mouse is mice, not mouses.
Option B is incorrect as although it is controversial, the plural of deer is the same as its singular form, so it is deer not deers.
Option C is incorrect as the plural of library is libraries, not librarys.
Option D is correct as women, children and familes are the correct plurals of their singular forms.
Hope this helps! :)
Have a lovely day! <3