Which of the following sentences defines a term by including an appositive?

A.The word irascible means "marked by hot temper."
B.Proper nouns (like Philadelphia,
James, and the Empire State Building)
always begin with a capital letter.
C.A stylus, a type of writing
instrument,was originally used to write on clay or waxed tablets.
D.In this paper, the modern era refers to anything that has occured since 1990.
Answer :C
Am I correct