What is an example of a possessive noun?

A possessive noun indicates ownership and is formed by adding an apostrophe and sometimes an "s" to a noun. In the example "Jessica's book," the possession is clear: it shows that the book belongs to Jessica. The apostrophe and "s" signal that relationship of ownership effectively.

The other choices do not demonstrate possession. "Books" is simply a plural noun, "running" is a gerund or noun that refers to an action, and "easy" is an adjective. Therefore, "Jessica's book" clearly stands out as the example of a possessive noun, as it communicates a specific relationship between the noun and the owner.