It’s A, because D.

D!

Can you choose both B and C?

Christians: E, Mysterious ways.

E) all accept D

Christians: that's the one for me

A, B, and D.

Depending on the terrible thing sometimes C, but more often than not humans do it to other humans with full intent. But since that is not what the question trying to ask it's important to say when god doesn't prevent something terrible, it's for our own good. Like teachers won't do our homeworks for us because we won't learn otherwise. I know terrible things like World War 1 is far worse than a homework but if one world war was enough for us to learn not to fight each other there wouldn't be a World War 2, or any other war that came after (fortunately we have learned to some extent now because there are a lot less pro-war people now than before, evident by the anti-war protests followed by the Ukraine war which even happened in Russia). If god wanted to do our homework for us, they would have sent someone to fix everything with a single snap of a finger, but instead god sends teachers like Jesus and Muhammad, so we learn to do our homework by our self. While I haven't played skyrim a quote stuck with me which was "What is better - to be born good, or to overcome your evil nature through great effort?" Which I think is similar to this situation.

c

All of the above