(A) Even the internal structure could he modified in new ways; different materials could he incorporated as the process goes along.

(B) Researchers have developed a system that can 3-D print the basic structure of an entire building.

(C) Structures built with this system could be introduced faster and less expensively than traditional construction methods allow.

(D) Ultimately, the researchers say, this approach could enable the design and construction of new kinds of buildings that would not be feasible with traditional building methods.