They feared communism would spread.
That the nazis would come back and finish them off
In the Age of New Imperialism that began in the 1870s, European states established vast empires mainly in Africa, but also in Asia and the Middle East. - https://www.tamaqua.k12.pa.us/cms/lib07/PA01000119/Centricity/Domain/119/TheAgeofImperialism.pdf
The sentences that use commas correctly is A) Volcanoes spew molten rock and, mostly exist along the Pacific Rim.
