GMAT Sentence Correction (SC) | Re: More than 300 rivers drain into Siberia's Lake Baikal, which

Going with the 'cut the fluff' does the sentence makes sense?

More than 300 rivers drain into Siberia's Lake Baikal, which holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.
More than 300 rivers drain into Siberia's Lake Baikal more than all the North American Great Lakes combined.

Can anyone enlighten me?

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