听力原文： W: Hi, Dan, [23]you know which lab you missed？ You can have my notes.
M: Thanks. I appreciate that.
W: So how are you feeling？
M: Much better now that I began taking an antibiotic. Students Health gave me one, and it's really helpful. You know what amazes me？ [24] The human races survive before antibiotics.
W: [24] I agree. When my father was a young boy in the 1940's, he got blood poisoning and would have died. But his doctor had heard of this new drug called penicillin.
M: Wow, he was really lucky. And we have lots of antibiotics that kill bacteria.
W: Well, penicillin kills bacteria, but not all antibiotics do. Some are just slowing the bacteria down until our normal immune defense can finish the job. Tetracycline(四环素) works in that way.
M: Wow, how do you know all these？
W: My mother used to look up all our medicines. There are lots of books around. It's interesting. What antibiotic are you taking？
M: I don't remember. It's on the bottle. [25] I think I'll take a new look at the label and drop by the library to see if they have reference books on medicines. See you in the lab tomorrow.
(1)

A. Her lab notes.
B. A medical reference book.
C. A homework assignment.
D. The name of her doctor.