Read this: Cubism formed an important link between early-20th-century art and architecture. The historical, theoretical, and socio-political relationships between avant-garde practices in painting, sculpture and architecture had early ramifications in France, Germany, the Netherlands and Czechoslovakia. Though there are many points of intersection between Cubism and architecture, only a few direct links between them can be drawn. Most often the connections are made by reference to shared formal characteristics: faceting of form, spatial ambiguity, transparency, and multiplicity.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What two things did Cubism in the early 20th century form an important link between?
art and architecture.