GMAT Club Tests | Re V03-01

I think this is a poor-quality question and the explanation isn't clear enough, please elaborate. I am not able to understand, the question is like all the options given below will cast a doubt on the given conclusion except for 1 option. How does B, C cast a doubt

Statistics : Posted by Vikramaditya00 • on 16 Sep 2014, 01:58 • Replies 9 • Views 61190

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