Concept:Subject-verb agreement: a plural subject must take a plural verb.Explanation:The error is in part (a) of the sentence.The subject “The Olympic Games” is plural in form and meaning.Therefore, the verb should be plural: “reflect” instead of “reflects”.The corrected sentence is: “The Olympic Games reflect the highest spirit of human endeavour and achievement.”Parts (b) and (c) are correct and contain no errors.Answer:(a)