The correct answer is C. Elaborate—marked by complexity, full of detail or ornate
Step-by-step explanation:
In language, a synonym refers to a word or term with similar or identical meaning to another word. In the sentence presented the word "complicated" is used to describe the design of the decorations " The complicated design of these decorations" in terms of architecture, this suggests "complicated" refers to very detailed or elaborated rather than to challenging or difficult as it describes the complexity of decorations. Thus, the best synonym or the word that has the same meaning that "complicated" in this context is "Elaborate—marked by complexity, full of detail or ornate".