高手帮忙看看，这一小段的结论句是哪一句？

dirklaobadao

如题，小段如下：
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It costs much less to grow an acre of grapes in California than it costs to grow an acre of watermelons in Oklahoma. This fact should be obvious to anyone who reads last year's annual farm report, which clearly shows that many millions of dollars more were spent last year growing watermelons in Oklahoma than were spent growing grapes in California.
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高手说结论句是This fact should be obvious to anyone who reads last year's annual farm report（黑人问号）
但我觉得结论句应该是第一句才对啊

一抹斜阳

同意芦竹观点，前一句是结论，后一句是论据

Jackson张

个人感觉This fact should be obvious to anyone who reads last year's annual farm report才是结论句
should be 就有推测的意思在里面，而第一句只是一个background或者是一个support