This was an awesome story with continuous turns and endless mysteries!!!

I have always thought.. it would be so nice if we, the students, could just read a great piece of work like this and enjoy it the way as it is and think further about it ourselves.. not being interrupted by questions like this: "What is the predominant irony in this story?"
Unfortunately

,we are still required to do so..
Please help me

on this question..
I do fully understand the content of the story, but I cannot find the "predominant irony!"
Earthian villiage not being "Earthian?"
Families not being real? There are so many!
Which do you think is the predominant irony?
Please share your opinion with me. Thanks!