Answer:
B. The attitude of the speaker toward his or her subject.
Step-by-step explanation:
The tone of a text can be defined as the attitude of the speaker toward his or her subject.
Basically, the tone of a text expresses or reflects the mood of an author of a literary work and as such goes a long way to affect the countenance of the reader. Therefore, the tone being used by an author in a literary work such as articles, novels, stories etc., has the potential of evoking various emotions and shaping the perspective of a reader of the piece of writing.
Also, you should note that tone is a literary device in literature and simply does not mean the way people speak or pitch used by a speaker in contemporary english language.
For example, I'll hit you up at noon in your office tomorrow means I'll see you at your office tomorrow.