In modern novels, characterization tends to be sparse because modernist literature

a. does not emphasize physical descriptions
b. emphasizes society as a whole
c. does not use dialogue
d. uses narration to teach moral lessons

I think the answer is letter C. 
Many modernist writers focus more on moral lessons. They delve deeper on the effects of what is going on around them. They were able to see the decline of technology and were able to point out the consequences of modernity and technology in society.