Russians are Slavs!
So the correct answer is "Slavic". Other Slavic groups that might live in western Russia in great numbers are the Belarussians and Ukrainians (although sometimes the difference of whether some groups are Russian/Belarussian or Ukrainian is not clear as all the groups speak at least partially Russian).
In any case, there are very few Anglo(-Saxon), Kurdish or Germanic people there, and those that are are a more recent immigration.
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