Find the part of the sentence that contains an error:

What the organization did not examine thoroughly enough (1)/ were not the scheme’s objectives themselves, (2)/ but the political consequences it (3)/ might have caused if carried out without wider agreement. (4)

The correct answer is (2).

Step-by-Step Explanation:

1. Identify the Subject of the Main Clause:
The sentence begins with the noun clause: "What the organization did not examine thoroughly enough". When a clause starting with "What" functions as the singular subject of a sentence representing a single thing or concept, it takes a singular verb.

2. Analyze the Verb Agreement in Part (2):
Part (2) uses the plural verb form "were not". Since the subject noun clause ("What the organization did not examine...") is singular in structure, the verb following it should also be singular ("was not"), regardless of whether the complement ("the scheme's objectives") is plural.

3. Correct Form of the Sentence:
The sentence should correctly read:
"What the organization did not examine thoroughly enough was not the scheme’s objectives themselves, but the political consequences..."

Therefore, the error lies in part (2).