What is the main conflict in the book "stiff" by mary roach?

Mary Roach begins her research of human cadavers by attending a facial anatomy and facelift refresher course, where surgeons practice new techniques on the freshly severed heads of human cadavers. Roach learns that surgeons cope by objectifying human remains, willfully seeing them as objects. The author sees the obvious benefit of learning surgical techniques using cadavers. Since they feel no pain and cannot die due to complications, cadavers offer immediate benefits for surgical study. She sees this as a great improvement over how surgery was once taught on live patients without the benefit of anesthesia.

where is the passage?

expository writing is one of the most common types of writing.