有道理！ OG中的解释是这样的 This sentence compares two actions, preventing crimes against property and preventing crimes against a person, in terms of difficulty. These actions should be described in grammatically parallel structures. Consequently, choices A, B, and D are faulty because they fail to parallel the first clause, which has it as a subject and is as a verb. Choice C contains it is but lacks to prevent those, words needed to complete the required clause and identify the other action in the comparison. Choice E is best: all of the elements necessary to describe the second action are presented in a form that is both idiomatic and grammatically parallel to the description of the first action. The question is moderately difficult. as引导的句子都有这个要求嘛：补出助动词，而且要补全！ | 
