The author cites studies that found the technique effective in a reasonably broad range of applications and argues that it is further supported by several psychological explanations in lines 11-20. The author uses the last paragraph to offer another explanation of why the technique may work, independent of studies and psychological explanations in the previous paragraph. The limitation author then mentions only relates to this specific context - when the technique is used to try to frame negative information in positive light to create a positive impression early on, it is not related to research results discussed in paragraph two as (C) appears to suggest.
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