参考答案

正确答案：too complicated and perplexing to handle
too complicated and perplexing to handle 解析：根据题干关键词computer criminal，caught，case，alleged crime定位到原文Difficulty of detection and prevention下第六段第一句：But even when an offender is canght, the investigators, may find the alleged crime too complicated and perplexing to handle. 该句指出：即使嫌疑人破抓，调查者、律师、法官或者陪审团可能发现被指控的罪行太复杂不好处理。所以too complicated and perplexing to handle是正确答案。