An analogy is defined as a similarity between like features of two things, on which a comparison may be based or as any similarity or comparability (WordReference Random House Learner's Dictionary of American English.) From the four options (the others are <em>performance, sports, pageant</em>) the one that mentions a similarity between tennis and chess is tournament.
The author uses a serious and morbid tone, as to let the audience feel the anguish of the soldiers. The tone helps the audience to create an image in their mind.
