Respuesta :
Answer:
(A)
Step-by-step explanation:
(D) is already out since the teachers may have favorites or unfavorites.
(C) is already out since you can't be in all the halls at once.
There is only (A) and (B).
I think it's (A) and not (B) because it might not be a classes/grades library day.
B.Students sitting at randomly selected tables in the library