Martha Writes a Letter to a Movie Producer Sharing a Screenplay

Multiple Choice

Martha writes a letter to a movie producer sharing a screenplay that she has written. Her letter ends with the words "Enclosed please find a copy of the script. Very truly yours, Martha." In terms of readability, what mistake has Martha made in her letter?

A) She has used clichés.
B) She has used active voice.
C) She has used outdated expressions.
D) She has used very informal words.