In which sentence does the word hollow mean fake? a) the sound of their hollow footsteps

In which sentence does the word hollow mean fake? a) the sound of their hollow footsteps filled the empty building. b) she watched as the creature began to hollow out a nest in the sand. c) michael was amazed to discover that the door was hollow on the inside. d) we knew his apology had been a hollow gesture when he began bullying us again the next day.