Janet Is Studying at the Library When She Remembers That

Janet is studying at the library when she remembers that she needs to make a phone call. She can be more confident about leaving her books on the desk if she:

A) makes them look old and useless.
B) asks the student adjacent to her desk to look after her books.
C) puts a note on the desk saying that the universe is watching.
D) hides them under her cardigan, out of sight.