Final answer:
An example of a U.S. import is Foreign oil purchased by the U.S. The concept of comparative advantage explains why countries trade, often resulting in significant intra-industry trade, such as the U.S. both importing and exporting autos.
Step-by-step explanation:
The correct answer to which of the following is an example of a U.S. import is Foreign oil purchased by the U.S. An import is defined as a good or service brought into one country from another. The other options listed, such as cars exported to Europe, iPhones manufactured in the U.S., and clothing produced domestically, do not qualify as imports. These are either examples of exports or domestically produced goods.
Another example of U.S. imports, according to the provided information, would be the imported oil from the Russian Federation. This ties back to the theory of comparative advantage, suggesting that countries should specialize in producing certain goods more efficiently and then trade with each other. In this case, the U.S. may find it more efficient to import oil rather than producing all the oil it needs domestically.
Moreover, there's a high proportion of intra-industry trade where, for instance, the United States imports and exports autos. This shows that even within a single industry like automotive, the U.S. engages in substantial trade, both importing and exporting different variations or brands of cars. As noted in the examples, the U.S. imports hundreds of billions of dollars worth of autos.