D).Have you ever wondered what swims in the deepest parts of the world's oceans?
What is central idea?
Central idea is actually know to be the major concept that serves as the narrative's uniting theme and connects all of the other fictional devices the author uses to tell the story. The dominating impression or the general, overarching truth revealed in the story are both good ways to define the key theme.
We see here that central idea helps readers to grasp what the author is passing across.
Thus, the above answer is the correct answer that shows the sentence that provides least support for the central idea.