Why would a modernist author write about the consequences of greed when an author from the age of reason wrote a book with a similar theme?

An author from the age of reason would write a book where the main topic would be greed, but he would do it in a very different manner from the modernist author, although the topic is relatively the same. This first author would write about greed, but only to present its bad sides, to say how and why greed is bad. Whereas a modernist author would talk about the same topic with the view to creating a society that knows no such sin, that is completely cleansed from it. 

The answer should be d.

  i think it is   b because it to subject