Find the part of the sentence that contains an error:
That there exists no recourse for citizens (1)/ if environmental violations are condoned at the ministerial level (2)/ underline a systemic erosion of (3)/ constitutional accountability. (4)

Correct option is C

Option (3) contains an error.
Detailed explanation of error: The subject of the sentence is the clause “That there exists no recourse for citizens …” which is singular. Therefore, the verb must also be singular. But part (3) uses “underline” (plural verb). It should be “underlines” (singular verb) to match the singular clause-subject.
Correct sentence: That there exists no recourse for citizens … underlines a systemic erosion of constitutional accountability.
Grammatical rule used: Subject–Verb Agreement
· A that-clause functioning as a subject is treated as singular.
· Example: That he refused to apologize shows his arrogance.
· Information booster / exception:
· Even if the clause contains plural nouns (citizens, violations), the entire clause as a subject remains singular, so the verb stays singular ( underlines/indicates/shows).