Since Britain first at Heaven's command
Arose from out the Azure Main,
Did ever o'er this jarring Land
A monarch with more firmness reign?
Then to the Natal Day we sing,
Of George our sacred friend and King
-from a song by American loyalist in honor of George III's birthday in 1777
That's right, the correct answer is C.
The Sender-Message-Channel-Receiver (SMCR) model identifies individual components of a communication act, which in turn are affected by diverse factors that combined can result in a more or less efficient communication. The four components are sender, message, channel and receiver.
People from different cultures may understand the same message differently. Things can be accepted in one culture and considered very offensive in another. Therefore is important that communication is performed between a sender and a receiver who have the same cultural background or who have an understading on how to deal with the cultural background of the other interlocutor, in case it is not the own one.
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.
A between silken sad and uncertain because they are adjectives of equal rank