The strange thing about engels' writings is that, although they spoke of the uprising of the common worker, his writings were used by some of the most governments of the last century.
conservative
oppressive
democratic
liberal
denevolent

The correct option is: "OPPRESSIVE"

Friedrich Engels was a philosopher, sociologist, journalist, revolutionary and German socialist theoretician. Engels was the son of the owner of a major textile factory in Manchester, England. Friend and collaborator of Karl Marx, was coauthor with this works like The situation of the working class in England (1845) and the Manifesto of the Communist Party (1848), fundamental for the birth of Marxism and the socialist, communist and union. He was political leader of the First International (1864) and the Second International (1889). He also helped Marx financially to publish Capital in 1867, and after his death, he edited the second and third volumes. In addition, Engels organized the notes of Marx to compose Theories on surplus value, which he later published as "fourth volume" of Capital.

the use of email to replace slower surface mail.

i would go with the last one