继续挑战 大全 606

<!--[if !supportLists]-->1.                             <!--[endif]-->Research during the past several decades on the nature of language and the processes that produce and make it understandable has revealed great complexity instead of underlying simplicity.

(A) that produce and make it understandable has revealed great complexity instead of underlying simplicity

(B) of producing and understanding it have revealed not underlying simplicity but great complexity

(C) by which it is produced and understood has revealed not underlying simplicity but great complexity

(D) by which it is produced and understood have revealed great complexity rather than underlying simplicity（A）BDE r eliminated as the subject is research

(E) by which one produces and understands it have revealed great complexity instead of underlying simplicity



I have read all the comments in the following address. However, I am not convinced by the explanations which favor A.
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1, 'produce' has to have an object.
2, if, as claimed, 'produce' and 'make' used the same object 'it',     'understandable' would have to be shared as well since 'make it understandable' is a whole. otherwise, 'it' must not be ommitted after 'produce.
3, the usage of 'by' in C needs to be clarified. i don't agree with those who insist that it be denoted as ' 语言被过程理解'.
here is another usage from Longman:
BY:used to say what means or method someone uses to do something
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---> Clearly,     C should be understood as '语言是通过过程而产生并被人们所理解‘
In sum, I think that C is better than A.     More discussion is appreciated.