I believe it is the last sentence highlighted in the paragraph.
Will you tell the truth, so i don’t have to lied
Without Oxygen we would not live
So the answer is to live
Hope this helps!
The answer is option B) Simple
This sentence is saying just the simple idea of you traveling alone over there is ridiculous. They're saying why even bother introducing the mere or simple idea?
Best Of Luck,

The theme of "Nothing Gold Can Stay" is that nothing, especially something that is perfect and beautiful, can last forever.