A subject and topic are similar but different. Do you have a sentence?
Answer:
O Rainsford killed Zaroff because he was angry about being forced to play the game even after winning
Explanation:
The first option cannot be it, since it is two pieces of evidence. The third statement also cannot be it, because its explanation is speculation and not for sure fact. This leaves the second option as the answer.
For your question, the answer would be; "C. The heroism of unquestioning sacrifice". This is because the poem tells the story of a brigade consisting of 600 soldiers who rode on horseback into the “valley of death” for half a league. They were obeying a command to charge the enemy forces that had been seizing their guns.