Retailers reported moderate gains in their November sales, as much because of their sales of a year earlier being so bad as that shoppers were getting a head start on buying their holiday gifts.
(A) of their sales of a year earlier being so bad as that
(D) their sales a year earlier had been so bad as because
Today, because of improvements in agricultural technology, the same amount of acreage produces twice as many apples as it did in 1910.
Just as scientists, because of random fluctuations in the weather, cannot determine the transition from one season to the next by monitoring temperatures on a daily basis, so they cannot determine the onset of global warming by monitoring average annual temperatures.
Almost like clones in their similarity to one another, the cheetah species’ homogeneity makes them especially vulnerable to disease.
(E) members of the cheetah species are especially vulnerable to disease because of their homogeneity
because一樣可以表達「明確的因果」，沒有什麼「只有because子句才能表達明確因果」這件事。關鍵在於「because of 後方接的名詞核心是否為原因的根本（通常是表事件的action noun）」。
because of improvements in agricultural technology… 核心名詞在「進步」。
如果寫成because of agriculture whose technology has improved… 那就完蛋啦！「農業」是不能當原因的。
because of random fluctuations in the weather…核心名詞在「波動」。
如果寫成because of fluctuating weather…呢？天氣是原因嗎？天氣的變動才是原因吧！
那請問，當今天可以寫成because of random fluctuations in the weather…時，有必要寫成because the weather fluctuates randomly…嗎？
語意都明確合理之下，哪一句比較精簡，是否一看皆知。當今天because of 後方核心名詞正確表達原因的時候，多開一個because＋子句反而使結構複雜化。
希望大家要學會這個點啊！幫because of 平反！