The internment camp countermeasure was adopted for which of the following purposes?

The correct answer highlights the historical context of World War II when the United States government relocated and interned thousands of Japanese Americans. This decision was driven by the fear of espionage and sabotage following the attack on Pearl Harbor in 1941. The U.S. government, influenced by wartime hysteria and racial prejudice, viewed Japanese Americans as a potential threat to national security, despite the fact that many were U.S. citizens.

The internment policy resulted in the establishment of internment camps where Japanese Americans were forcibly relocated and held under harsh conditions without due process. This event is now recognized as a severe violation of civil liberties and is a significant part of American history that reflects the consequences of prejudice and wartime fear.

The other answer choices refer to different historical events or contexts, such as deporting suspected communists, conducting high-profile investigations, or detaining Confederate sympathizers, which are not related to the specific internment of Japanese Americans during World War II. Thus, the focus on the relocation and internment of ethnic Japanese individuals during this time period underscores the significance of the correct answer.