The correct answer is C. In this passage, Orwell persuades readers to use simple language by providing examples of abstract titles given to difficult political situations.
For example: Orwell begins this passage with the abstract title of "pacification." What does it mean to pacify a village, though? If the term pacification were used in the news with no further explanation, viewers might think pacification were no big deal. Orwell, however, provides examples of pacification, turning this abstract title into something concrete.
He takes an abstract phrase (pacification, transfer of population, rectification of frontiers, etc.) and gives the reader specific examples of what it actually means.