The lines "Take up our quarrel with the foe: / To you from failing hands we throw The torch;" supports the theme - the living carry on what the dead cannot. The torch signifies the living continuity of the cause they are fighting for. These lines give a challenge to the ones who are still living to not stop but keep going.
I think it is to entertain and inform, but mostly to inform.
Answer:
B seems to make the most sense
Explanation:
All the other options seem like good reasons but are not as important as improving your overall skills (from my perspective at least). Hope this helps!
