The correct option is D Chronological order, if followed too mechanically, obscures rather than clarifies important relationships
Here, the error is in the subject-verb agreement: The plural pronoun "they" is used incorrectly to refer to the singular noun "chronological order." Only D rectifies this error by omitting the plural pronoun ("they"), which did not agree with the singular noun "chronological order." The other options are incorrect as they either carry the original error or a new one.