Final answer:
Germany's annexation of neighboring countries, alliance with Spain, and trade blockade against Great Britain concerned Americans but did not change their resolve to stay out of the war.
Step-by-step explanation:
The German actions in the 1930s that concerned Americans but did not change their minds about staying out of the war were A Germany's annexation of neighboring countries, B Germany's alliance with Spain, and D Germany's trade blockade against Great Britain.
Germany's annexation of neighboring countries, such as Austria and Czechoslovakia, violated international agreements and sparked concerns among Americans. However, it did not directly impact their decision to stay out of the war.
Germany's alliance with Spain, under General Francisco Franco, alarmed Americans as they saw it as an extension of German influence. Yet, it did not change their resolve to remain neutral.
Germany's trade blockade against Great Britain, known as the Battle of the Atlantic, impacted American trade but did not alter their determination to avoid joining the war.
Learn more about German actions in the 1930s