Which would be a reason for an author to choose to use a third-person omniscient narrator?
a. the author would want the reader to see things from one perspective.
b. the author would want the reader to understand a particular character better.
c. the author would want the reader to have a more reliable and objective narrator.
d. the author would want the reader to get an in-depth understanding of a character.

 A third-person omniscient narrator is when the perspective changes between multiple different characters in a story. Third person limited is when the perspective stays with one character and is more common than third person omniscient narrating. The reasons for writing with third-person omniscient is to get perspective from all characters, to make the story more interesting as it moves along, and to understand multiple characters better. 

The best answer for this question would be letter d. because you may not understand the way a character stands until you get a perspective change.