Answer:
Krakauer begins the story of Chris McCandless at the end of his life to create a sense of mystery and intrigue for the reader, and to draw attention to the fact that McCandless died alone in the wilderness. By beginning with this dramatic event, Krakauer sets the stage for the rest of the story and piques the reader's interest in understanding how and why McCandless ended up in this situation. Additionally, starting at the end allows Krakauer to explore the circumstances of McCandless's death, and to delve deeper into the factors that led to his decision to venture into the Alaskan wilderness alone.