To convey inner thoughts of the characters to the reader, or to have characters communicate to each other to help the reader gain information upon each of their personalities, inner thoughts, and their views upon the world/setting/plot.
Lucia was suffering from tuberclousis
The rhetorical element that is included in the passage is : D. Logos
We can see in the passage that Lincoln recognize the issue and address the issue with his principle of reason, logic, and judgement
hope this helps