Answer:
“The five foxes' tails”
Step-by-step explanation:
A possessive noun is a noun that is added an “s” and an apostrophe or an apostrophe only at the end in order to show ownership of something or someone. The general rule is that when the noun ends with an “s”, only an apostrophe is added, but when it does not end with an “s,” then an apostrophe and an “s” is added, for example, “the girl's house,” and “the girls' house.”
Therefore, in order to rewrite the phrase “tails of five foxes” using a possessive pronoun, we must add an apostrophe to “the five foxes” (the noun that posses) because it ends with an “s:”
“The five foxes' tails”