【正确答案】 D

【答案解析】[解析]摄影的普及不仅改变了人们的交流方式，也：选项A：促进经济大幅增长。正确，第四段最后一句：The impact of the sale of photographic equipment on the economy is equally mind-boggling．摄影器材的销售，对经济产生的增长幅度会把人吓一大跳。选项B：提高信息的转换效益。正确，文章最后一段第一行：It has greatly enhanced our ability to convey information．选项C：增进人类之间的理解。正确，文章倒数第二行：photographs have greatly extended our understanding of and compassion for our fellow human beings．故应选D。