The option that does not explain an effect of the author's use of dialogue is A.
It helps the reader understand what characters are thinking in the story.
Dialogues show the character's personality, emotions, and actions. Dialogues allow to show how the character is instead of describing how the character is.
In addition to this, the main idea of using dialogue is to show reality such as a conversation between characters. Dialogue affects the characters due to they understand and connect with the other characters.
