In City, what can be inferred from the author's choice to include drawings of tools used by ancient Roman city builders? A. He wants to show that the ancient Romans used many tools that seem strange to modern readers. B. He wants to show that cities can only be built with tools that are made from wood and stone. C. He wants to show that tools are not totally necessary when building a city. D. He wants to show that modern builders use many of the same tools that the ancient Romans used.