Answer:
"I'm not sure what really happened, but I do know that I'll think twice before entering someone else's house without permission."
Explanation:
Let's view this from a formal, educational point of view. Pieces of text and writing should not have redundant phrases. Educational and formal conclusions should add some finality and sum up what you said properly.
With this in mind, the last one would be a terrible conclusion because it's uninteresting.
The first one is very common and is not interesting either.
The second one is also kind of common.
The third one adds a LESSON!! The third one gives you what the author has learned over the essay/story. The third one would be the best conclusion
