Despite what else may have occurred within the story up to
that point, this excerpt provides insight into the characteristics of the
narrator. With the terms “earnest
endeavors,” it is revealed that the narrator is making sincere efforts to
alleviate the friend’s sadness. What
this means, thus, is that the narrator can be seen in this light as a true,
caring friend whose actions are without ulterior motives.
It's A. subordinate because it begins with a subordinate conjunction "because" and its adverbial clause since it asks the question "why?"
The best revenge is to just happily move on and let Karma do the rest.