GMAT Critical Reasoning (CR) | Re: Pundit: Many people blame the construction of retail locations

I chose B. Don't know how OA is correct. E says that "It introduces a judgement that the argument opposes.", however, argument never seems to oppose it in any way. It just supports another factor[Online sales] along with establishment of retail locations.

B is on the other hand states that " It is a finding that the argument seeks to explain.". Surely, the reader expects an explanation for the first line. The word "finding" however seems to be odd here since it