I'm thinking it was Great Britain.
Stopping the spread of communism was the top priority outlined in "<span>the Truman doctrine," since Truman was one of the US presidents who was in office during the Cold War and wanted to "contain" communism. </span>
Answer:
(A) Relocated
Explanation:
You didn't include the sentence that was meant to be shown but based on the connotation and definition of the word 'migrated', the answer is most likely relocated.
Hope this helps :)
C. This would enable to find the events and get his thoughts and report in order.