Impact craters caused by meteorites smashing into Earth have been found all around the globe, but they have been foun...

Hello! For some reason, my head is seeing the correct answer choice (D) as a Necessary premise, and not a Sufficient one. I am interpreting it as taking out an alternate cause of the meteors hitting the earth in concentrated spots. I see how the other answers are wrong, but could it be explained to me how this choice GUARANTEES the stimulus? Thank you!