We are trying to find the answer choice that best matches the principle contained in the stimulus.
Here the principle in the stimulus goes along the lines of: Going through a mini version of something to make one stronger in future scenarios.
This is how answer choice B matches. The parents in this answer choice put their kids through a lessened version of encountering treachery and cruelty (through story form) to make them stronger as adults.
I hope this helps. Please let me know if you have any other questions!