GMAT Sentence Correction (SC) | Re: Despite its covering the entire planet. Earth has a crust

If this was one of the choice -

(C) Despite covering the entire planet, Earth's crust
is neither seamless nor is it stationary, but
rather is

Could it have been a correct choice.. I guess I would like to know the usage of neither..

Correct/ Incorrect??
She neither is leaving nor is completing the work.
She is neither leaving nor is she completing the work.
She is neither leaving nor completing the work.

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