我觉得得把这一句解释结合它上一句看。The sentence compares the number of apples produced today with the number of apples produced in 1910.The phrase double the apples is not very exact...
我觉得double其实问题很大。 OG上说the phrase double the apples is not very exct but it could be understood to mean twice as many or as many as。但这里只提到了double the apples,没有提到跟后面的跟1910年比较的部分。double the apples是正确的,因为double有“使加倍”意思。 一旦跟后面的that it has in 1910(我们忽略has的问题,看做他是对的,当作it did in 1910)连起来就不对了。注意这里是一个限定性定语从句,表达的意思是“它在1910年生产的苹果”,这已经是一个过去的时间,是历史事实,不能改变的,现在的技术没有办法double过去的产量。所以A选项的解释中才说the comparative construction as many as is needed.