All of the Following Are Examples of Pragmatics EXCEPT

All of the following are examples of pragmatics EXCEPT

A) four-year-old children simplify their language when speaking to younger children.
B) by their teens, children are able to use the passive voice.
C) first graders explain things more fully to a stranger than to a friend.
D) first graders are more polite to adults and to strangers than they are to their own peers.
E) children are more polite to strangers than to their peers.