According to the professor’s philosophy, the antidote to envy is one’s own work, always one’s own work: not thinking about it, not assessing it, but simply doing it.

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

C is wrong bcoz Not x But Y X & Y not in parallel
D is wrong for same reason
E is wrong since 'it' in the last clause in ambigious

Why was B wrong? ['it' ambigious? 'work' is not specified as one' own work?]

Official answer is A.

trying to ensure I get all the reasons for the options that are wrong!