GMAT Sentence Correction (SC) | Re: In most social systems, minority groups eventually demand

Mike,

'Those' is a demonstrative pronoun. So doesn't it have to have an antecedent? I ruled out E because of the usage of 'those'. It cannot refer back to either the 'social systems' or the 'minority groups'.

My inability to judge on issues like these always costs me a lot. I'm never able to figure out there subtleties in the GMAT SC questions, because of which i'm always struggling to get questions right.
Please advise.