Which choice contains an error in parallel structure?
A) There are three aspects to being a good comedian: having good material, displaying a proper sense of timing, and respecting your audience.
B) Please go to the grocery store and purchase milk, cheese, cereal, and ice cream.
C) You need to pay better attention, to follow directions, and listening well.
D) My favorite teachers are witty, knowledgeable, and open-minded.