In which situation may changing item height be more suitable than changing workplace height?

Correct answer: When main surface is correct but frequently used item is kept too low

The direct answer is option A: change the item height when the main work surface is suitable but a frequently used item is kept too low. Ergonomic improvement should be specific, not unnecessarily large. First identify the exact source of awkward posture or repeated bending. If the table itself has a suitable height and only one often-used object is low, raising or repositioning that object may solve the problem with less effort and cost. Option A is correct because it targets the actual risk. Option B is wrong because if the whole table is unsuitable, changing only one object may not solve the general problem. Option C is wrong because items already within correct reach do not create this height problem. Option D is wrong because whether a person stands does not by itself tell us whether an item is wrongly placed; the posture and task must be assessed. Exam cue: modify the smallest part that causes the real ergonomic difficulty.