I believe B is not the correct answer - C. Brutus' story is the focus of the play is.
A is definitely incorrect because both his story and his actions greatly impact the play - he is the one who decided to have Caesar murdered, after all. I don't think B is correct either - even though he did kill Caesar, he is not a classic villain. He is not evil, he did not kill him because he hated him, he killed him because it had to be done - he believed Caesar was on the path of becoming a tyrant. So he killed him to save Rome, which is not a villainous thing to do. D is also incorrect because Brutus is one of the main characters, if not the main character.<span />
You would want to use B. sentimental here because it's defined as nostalgia or a feeling of tenderness or sadness for something, which in this case would be all of the memories that Jeremiah had in high school.
