GMAT Sentence Correction (SC) | Re: The discovery that Earths inner core rotates independently

The discovery that Earth’s innercore rotates independently of and more quickly than Earth’s outer layers is responsible for advancing studies of the flow of heat from the inner through the outer planet and of the formation and periodic reversal in direction of Earth’s magnetic field .

A. core rotates independently of and more quickly than Earth’s outer layers is responsible for advancing studies of the flow of heat from the inner through the outer planet and of the formation and periodic
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