The most appropriate antonym for "hospitality" is "coldness." Hospitality refers to the warm and friendly reception and treatment of guests, so "coldness," which implies a lack of warmth or friendliness, serves as the opposite. The other options— "complaint" (a statement expressing dissatisfaction or annoyance), "cordiality" (warmth and friendliness), and "wrathful" (full of or characterized by intense anger)— do not convey the opposite meaning of "hospitality" in this context.

"Upgrade" involves improving or raising to a higher level, so the opposite or antonym would be "Demote," which involves lowering or reducing to a lower level. Therefore, option (C) Demote is the most suitable antonym in this context.

"Shallow" refers to something having little depth, while "deep" represents the opposite, indicating a significant depth.