Final answer:
The best defense for Oregon's ad valorem property tax on Japanese cargo containers is that the tax is reciprocal to Japan's tax on American containers, which suggests fairness and compliance with U.S. law. Option A is correct.
Step-by-step explanation:
The strongest argument that could be made in defense of the Oregon ad valorem property tax on Japanese company's cargo containers is that the tax is reciprocal to the pre-existing tax applied by a Japanese city to American company containers. This argument rests on the concept of reciprocity and is based on the fact that similar tax treatment is applied in both countries, thereby suggesting that Oregon's tax is not unfairly targeting foreign commerce or violating the constitutional provisions under the Commerce Clause.
The case of Japan Line, Ltd. vs. County of Los Angeles can be distinguished if in that instance there was no similar taxation occurring in Japan, making the situation different from the present scenario where reciprocal taxes exist.