The Republicans in the Spanish Civil War were supported by various anti-fascist groups, including international volunteers who aimed to combat fascism. These volunteers played a crucial role as they were motivated by the need to fight against authoritarian regimes in Europe. The conflict was a significant part of the struggle between democratic ideals and fascism during that era. ;
The Republicans in the Spanish Civil War received support primarily from international volunteers who fought alongside them against fascism. This group included individuals who came from various countries motivated by anti-fascist beliefs. Therefore, the correct answer is: D. international volunteers.
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