Which of the following sentences illustrates incorrect pronoun usage?

Which of the following sentences illustrates incorrect pronoun usage?

A. The wet dog shook itself off, wagged its tail, and proceeded on its way.
B. Don't take the silver goblet out of its protective case or you'll ruin it.
C. You should wear that jacket to their wedding because it's the nicest one you have.
D. It's not too late to answer their ad for a waitress, is it?
E. None of the above

Answer - E