参考答案

正确答案：B
问题问及mainconcern(主要的关注内容)，利用该词作为答案线索，这样发现答案相关句：Showeredwithhonours，Cousteauremarkedrecentlythathethoughthismostimportantaccomplishment(与题干中的mainconcern呼应)wastomakepeopleawareofandcareabouttheocean．(该划线句的内容揭示海洋是Cousteau的研究中心)Thankstohim，wegrewconcernedaboutourgrowingpopulationandtheconsequencesofoverfishingandoceanpollutionthatthreatenthehealthofthesea,andwewereinspiredtodosomethingtoimprovethewaythingsaredone．该句暗示海洋污染也是Cousteau的研究内容，综合上面的分析确认答案是B。