Find the part of the sentence that contains an error: That the report overlooked several underlying causes (1)/ behind the public unrest were surprising (2)/ given the volume of evidence (3)/ collected over the past few months. (4)

Option (b) contains an error. The subject of the sentence is the entire that-clause: “That the report overlooked several underlying causes…”. A clause used as a subject is treated as singular, so it must take a singular verb. • Incorrect: were surprising • Correct: was surprising Corrected sentence: “That the report overlooked several underlying causes behind the public unrest was surprising given the volume of evidence collected over the past few months.” Grammatical rule applied: When a that/what/why/how clause functions as the subject, the verb is singular, even if plural nouns appear within the clause. Example: That they delayed the decision was unexpected. Why the other parts are correct: • (1) Correct clause-subject structure. • (3) “given the volume of evidence” is a correct reason phrase. • (4) “collected over the past few months” correctly modifies “evidence.”