D) The speaker's paranoia becomes more pronounced.
Explanation:
Edgar Allan Poe is considered one of the greates horror writers to ever lived, he wrote mostly suspense and fantasy, but for his time and historic context his writtings were revolutionary, in the Raven, which is one of his greatest poems he describes a person, the narrator going crazy over the presence of a Raven that he can not quite put his finger on what is wrong with. The organization of the poem makes the narrator´s paranoid more evident as the reading advances.
I would say that the theme that Leo Tolstoy explores in this excerpt from The Death of Ivan Ilyich is that C) human mortality is inevitable, and it is important to live an authentic life. Hope that Helps