I say C. because the entire paragraph is talking about political power.
Answer
Nations at war targeted neighboring nations of the enemy as an offensive strategy
Explanation:
The alliances were made so you had support if a war broke out. Germany during World War I was known for its offensive strategy due to a strong nationalism. They also had imperialist ideas about creating a great Germany. The other nations was forced to declare war on Germany as they made a pact with Austria-Hungary. When Germany made that pact and helped Austria-Hungary, the other alliances was forced to fight Germany as a defensive strategy against them.
All of these organizations sought to protect organized labor after the industrialization of America had led to dangerous working conditions for many workers. They were mostly succesfull, in at least bringing attention to these issues.
The main result of the Supreme Court decisions in McCulloch v. Maryland and Gibbons v. Ogden was that the federal government was allowed to continue to exercise its power to regulate interstate commerce over the states.