Using our context clues, the theory of a central fire most likely means: that the center of the earth was made of fire that a fire must exist in the center of all thing that if one is going to build a fire, it should be centrally located that fire explodes eventually from journey to the center of the earth book

The correct answer is that the center of the earth was made of fire.

Explanation:

Journey to the Center of the Earth is a novel by French writer Jules Verne. The novel narrates the story of Axel, nephew of Otto Lidenbrock, who shows Axel a document that reveals the entrance to the center of the Earth.

In the book, Otto debates the idea of the central fire, which meant that the closer a person approached to the center of the earth, the higher the temperature would be. He considers this theory as an incorrect one, and the answer to this is revealed as the novel moves forward.

id say it means hes fearful and/or cautious

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