Option A is the one that best shows how the mother's attitude towards Gregor has changed. In this passage, we learn that Gregor's mother is alarmed by Grete's words, which motivates her to look at Gregor. Gregor, however, has already turned into an insect, which shocks the mother. She screams and falls onto the couch. This clearly shows that the mother's attitude towards Gregor has changed.
