(A) one’s own
work, always one’s own work: not thinking about it, not assessing it, but
simply doing it

(B) always work;
because you don’t think about it or assess it, you just do it

(C) always one’s
own work: not thinking about or assessing it, but simply to do it

(D) not to think
or assess, but doing one’s own work（A）

(E) neither to
think about one’s own work nor to assess it, it is always simply doing it

答案是A, 请问这句话应该怎么分析？如果把c中的to do it 改为doing it是否正确？