During the first Red Scare in 1919, the perceived threat emanated from which of the following?

The perceived threat during the first Red Scare in 1919 primarily stemmed from anarchist and communist terrorism and subversion. This period followed World War I and was marked by widespread fear of radical political movements, particularly those advocating for communist ideologies following the Russian Revolution of 1917. Anarchists and leftist movements were linked to a series of bombings and labor strikes that heightened public anxiety over potential uprisings and the influence of foreign ideologies within the United States.

The era witnessed numerous events, such as the Palmer Raids, where federal agents targeted suspected radicals. The government and the general populace were particularly wary of these ideologies because they threatened the established capitalist and democratic systems in the U.S. Furthermore, the association of these movements with chaos and violence led to an atmosphere of fear and suspicion that characterized the Red Scare.

In contrast, fascist and Nazi ideologies were not the primary concerns of the time as they gained prominence later in the 1920s and 1930s. Thus, the focus on anarchism and communism accurately reflects the cultural and political climate of the period, making this the correct answer.