28. Which one of instructions for precautions on maintenance described in the workingmanual is incorrect?
(A) Don’t need to prepare engine jigs and tools ready to use.
(B) While checking and maintenance servicing the engine, post a notice on a warning indicatingboard for danger prevention.
(C) Strive to prevent a danger from emerging, forbidding other than the parties concerned to enterthe engine room, for instance.
(D) Prepare oils, genuine parts, waste cloth, wire, etc. according to the nature of work to be done.