1. In the last few years, the number of convicted criminals given community service sentences, which allow the criminals to remain unconfined while they perform specific jobs benefiting the public, have risen dramatically.

(A) sentences, which allow the criminals to remain unconfined while they perform specific jobs benefiting the public, have

(B) sentences, performing specific jobs that benefit the public while being allowed to remain unconfined, have

(C) sentences, performing specific jobs beneficial to the public while they are allowed to remain unconfined, have

(D) sentences which allow them to remain unconfined in their performing of specific jobs beneficial to the public has（E）

(E) sentences allowing them to remain unconfined while performing specific jobs that benefit the public has

正确答案E,在E中while performing specific jobs that benefit the public has 该句用了主语和系动词省略形式.根据状语从句的省略要求,该句的主语必须和该句的主语一致,因为该部分在which引导的从句部分,故省略的主语应是which指代的先行词,而根据句意,这里实际省略了criminal,请问这么用省略对吗?