I believe its c. Decrease Indent.
<span>“By
long suffering my nerves had been unstrung, until I trembled at the
sound of my own voice . . . .”
His nerves are unstrung, he trembled at the sound of his own voice, this could mean many things however it is likely he is Saying (or Thinking) things that scare him when snapping back to reality, like a man who was about to commit suicide but then remembers reality and he fears his own mind of what he was thinking.
“Another step before my fall, and the
world had seen me no more . . . .”
sounds cool, but is too vague.
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<span>“[T]here was the choice of death with its direst physical agonies, or death with its most hideous moral horrors.” This is close to the first one, he sees how far he is to madness, but is still on the edge and not insane Yet. However it's not as clear as the first one I listed
</span>
<span>“I saw clearly the doom which had been prepared for me . . . .” displays nothing.</span>
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.
