The rise of "mega-gym" chains, which offer low

Solution

As per the argument, it is not true that it is because of the entry of “mega-gyms”, whose large scale keeps their fees low, that many boutique fitness studios have gone out of business. This is because mega-gyms account for only a tiny fraction of the total fitness center memberships. This argument can be best weakened by option (e) which says that to compete with the mega-gyms' widely publicized low fees, boutique studios have been forced to lower their own prices to unsustainable levels. This explains how despite having a small share of the market, the mega-gyms managed to eliminate many boutique studios from the business. Thus, option (e) is the right answer.