All business owners invited to bid for the lucrative construction project realize that, in order to secure the contract, they must have presented an exceptionally well proposal.
have presented an exceptionally well proposal
have presented their proposal exceptionally well
present an exceptionally well proposal
present an exceptionally good proposal
present a good proposal exceptionally
OA is D. However that is incorrect because it is redundant (either present a good proposal or present an exceptional proposal, but not present an exceptionally good proposal).
(E) eliminates this redundancy and while it makes exceptionally modify present, there are no errors.