The theme that is developed in this excerpt from Macbeth's soliloquy in Act III, Scene 1 is:
B. Betrayal and revenge.
Macbeth is known to be a tragedy play written by William Shakespeare. It showcases the negative impact of political ambition for those who seek for power.
In this excerpt, we can see that the soliloquy actually reveals that there is a moral decline in the life of Macbeth. He seems to be guilty for killing Duncan, but now he seems remorseless about killing Banquo. This is to show that power corrupts.
Learn more about Macbeth on https://brainly.com/question/25961474