听力原文：Good morning, students. The school bulletin lists this course as a required writi

听力原文： Good morning, students. The school bulletin lists this course as a required writing course for second-year students. This does not mean the first-year or third-year students may not take it. What it means is that those of you who have never learned how to write a research paper are to be here, and those of you who already know how should leave immediately and sign up for another English course. I hope to cover the entire process of writing a research paper from selecting a topic to putting together the final format and presentation. I'll be here to help you every step of the way. But it is your responsibility to hand in each assignment on time. Your final grade will be the grade you receive on your paper.

Who was the speaker？

A．A librarian.

B．A professor.

C．A researcher.