in a vacuum, door/whistle/rope are the 3 best for bell, but time is definitely up there close enough to that tier that I won't fight it too much
door/whistle/time = 5pm (out the door, whistle blows to end the work day, it's a time)
door/whistle/rope = bell; really no other clue for door/whistle/rope than bell
so he def clues this if it's door/whistle/rope
if it's door/whistle/time, then alarm works just as well for door, better for time, and really strong for whistle, and it avoids rope