Which of the following sentences contains the appropriate use of an apostrophe?

The sentence that demonstrates the appropriate use of an apostrophe is the one that mentions "Boss's Day." In this context, the apostrophe is used to indicate possession, showing that the day belongs to or is dedicated to the boss. This usage is correct because it properly illustrates that it is the boss who is being honored on this particular day.

In the other examples, the use of apostrophes is either incorrect or unnecessary. The first option improperly uses an apostrophe to denote possession for a plural noun. The second option mistakenly uses "it's," which is a contraction for "it is," when the intent was to indicate possession (the ugly head of the storm). The third option incorrectly uses "they're," which is a contraction for "they are," instead of the correct possessive form "their" to refer to the sports equipment belonging to the players. Understanding these distinctions helps clarify the correct application of apostrophes in writing.