A historian wants to learn more about the economics of an ancient civilization. Which of the following items would provide the historian more clues about the civilization's economy?
A. finding ancient writings, such as symbols and pictures, that are carved on old stones
B. discovering tools, such as knives and arrows, that show the people's skill with metal
C. uncovering several coins in a region where early human remains are found
D. locating documents that include the laws of the ancient people in a region