Which option shows the proper possessive plural punctuation?

• A. For plural possessive nouns, add apostrophe after the 's'.
• B. For plural possessive nouns, add only an 's.
• C. For plural possessive nouns, add an apostrophe without an additional 's'.
• D. For plural possessive nouns, add apostrophe after the word.

Answer: (C)

For plural nouns that already end in s, form the possessive by adding only the apostrophe after that final s. You do not add another s. This gives examples like cats' hats or the teachers' lounge. The best phrasing communicates this exactly: place the apostrophe after the final s and omit an extra s. (If the plural is irregular, such as children, you would use the 's form—children's—so that’s a different rule.)