The letter was sent from Frex to her daughter Elphaba, requesting her to help with her younger sister Nessarose Thropp - the woman who becomes the Wicked Witch of the East - who has taken her position as Eminent Thropp of Munchkinland. In the package, Frex sends Nessarose the sparkling glass covered shoes which were made by Yackle (technically, out of glass) as well as ornamented by Frex using techniques he has learned from Turtle Heart. They become a major source of conflict due to Elphaba's jealousy, as she is determined to get them back at all costs, but Dorothy is unable to remove them.
Grete Samsa, Gregor's sister, most definitely goes through a "metamorphosis" as does every member of the family. Before Gregor's change, Grete is described as a "useless" daughter. She has taken violin lessons, but she isn't very good. She doesn't leave the house often. She is timid and seemingly afraid of the world.
I believe the answer is D
