i believe the answer would be fruit grows
The term "castle-in-the-air" is actually a term that means something that is imaginary and extravagant and most likely are not realized or carried out. In other words, this is similar to the term "daydream". When we use TV as <span>"castle-in-the-air", the danger for this is that people tend to view something as a reality instead of just accepting it as fantasy. Hope this helps.</span>

Sentence is a group of words which makes a complete sense.
The line that best paraphrases the excerpt is A. And when I think that I’ll never see you again, beautiful creature (...).
To paraphrase is to express the meaning of something by rewording it in a different way. Both the excerpt and option A express the same: that the poet is considering the possibility of never looking at the beautiful "creature" again.
It's avail, avail means make use of