I think I get it. Kvinnen drikker ikke brus... This caused me a problem too until I read it more carefully. Note the lack of 'en' before 'brus', which indicates soda in general rather than an individual soda.
It should be. I don't think they mean soda water but soda is the american term for any fizzy beverage and not a word a British person would use. The first thing I thought was baking soda and that is obviously not right.