Read the excerpt from an informational document.

Trade was necessary to the functioning of the Japanese economy. When Japan entered the first stage of its modernization in the nineteenth century, it had become dependent on other parts of the world for markets and raw materials. Raw materials for heavy industry were so strategically important they were placed in separate category from the rest of Japan’s imports. As a result, it was essential to ensure the security of the areas that supplied Japan and the trade routes that must be traveled, to ensure a reliable supply. Iron for the steel industry was of particular concern as Japan was almost wholly dependent upon imports . . . . The nearest major sources of iron were in Manchuria and northern China.

—From Japanese Imperialism, 1987

Which facts support the thesis that trade helped Japan modernize its economy? Check all that apply.

Japan considered raw materials to be important.
Japan began modernizing in the eighteenth century.
Japan depended on imports to obtain iron.
Japan ensured the security of trade routes.
Japan located major sources of iron in China.

All these alternatives show that Japan used iron as a material of paramount importance for the industrial development of its economy. Thus, in considering the strategic need for industry raw materials, especially those that the country did not have, such as iron, Japan adopted trade strategies to ensure the supply of these inputs to its industry. This was done by mapping suppliers, such as China, and adopting and securing sea routes through which inputs and industrial production would flow into international trade.