This question test Modifiers...check for what is modified and you will get the answer or atleast eliminate the wrongs one is one shot.
Coming to the answer.. the correct answer is indeed D. It correctly modifies 'Divorce'.
A). Looks like the divorce occured to them, (and not to their parents) when they were child .
B). Is the same as above (with a difference is plural)
C). Error in here is singular ( as the author uses "Young men AND women) Children is correct)
D). Correct form
E). 'HAS OCCURED", wrong tense.. the author says divorce occured long time ago .. this is a tense error along with the other ones)
Giving another SHOT