Obsidian was a natural resource not found in the Olmec civilization. However, the Olmec people used obsidian to make tools. This led to the discovery that the Olmec civilization had established large A. irrigation systems. B. water routes. C. trading networks. D. subsistence farms.

The Olmec civilization had established C. Trading Networks

Explanation: Olmec artifacts have been found across Mesoamerica, indicating that there were extensive interregional trade routes.

trade regulation is a field of law, often bracketed with antitrust (as in the phrase “antitrust and trade regulation law”), including government regulation of unfair methods of competition and unfair or deceptive business acts or practices. antitrust law is often considered a subset of trade regulation law. franchise and distribution law, consumer protection law, and advertising law are sometimes considered parts of trade regulation law.

in general the theory of economics says that the more open to trade a country is the better   the result for the same country and the whole economies.

in real life countries impose taxes, quotas, etc which is not so good for the economies.

this kind of commercial war between the usa and china is slowing down the growth of the whole world so we can say that it is a draw back of trade regulations. and the free trade agreements are benefits of trade regulations.

permafrost layer, it exists beneath a layer of soil, rock or sediment.