Earlier quoted context omitted.
You are right that, for the purpose of this exercise, the author's intent is not the issue (though it explicitly is in the next question.) This question is not the best one to make the point; take, for example, question 35 -- personally, I would pick B but can understand why someone might pick C, which might, for all I know, be the nominal answer. The worst cases seem to be where the question-setter has a fixed idea…
Question 35 is testing whether you know how "metaphors" work. B is correct because "putting toys back into the chest" is a metaphor for the weekend's fun-and-games being over. C cannot be correct because it's referring to the text's literal meaning ("organizing things") without giving effect to the "metaphor" call-out in the prompt.
35 The imagery in lines 16 through 19 helps the reader understand –
A the shift in the speaker’s attitude
B the speaker’s unpleasantness
C why the speaker has no friends
D what the speaker thinks of others