Identify the part of the sentence that contains an error in "I am certain that the officer is not only greedy but corrupt."

Introduction / Context:
This error spotting question checks your knowledge of correlative conjunctions, specifically the pair "not only … but also". The sentence given is: "I am certain that the officer is not only greedy but corrupt." You must decide which part of the sentence breaks the expected parallel structure and therefore contains the error.

Given Data / Assumptions:
The sentence is split into:

• (A) I am certain that
• (B) the officer is not only
• (C) greedy but corrupt.
• (D) No error

We must select the segment where the grammatical pattern is incomplete or wrong.

Concept / Approach:
The correlative conjunction "not only … but also" works in pairs and is used to join two parallel elements. When we say "not only X but also Y", both X and Y should be grammatically similar (both adjectives, both nouns, etc.). In this sentence, "greedy" and "corrupt" are parallel adjectives describing the officer. However, the word "also" is missing after "but", which makes the standard correlative pair incomplete.

Step-by-Step Solution:
Step 1: Identify the correlative conjunction: "not only … but …". The second part is expected to be "but also". Step 2: Look at part (B): "the officer is not only" – this correctly begins the correlative structure. Step 3: Examine part (C): "greedy but corrupt." Here, "but" is present, but "also" is missing after it, which breaks the correlative pair. Step 4: Parts (A) and (B) are structurally fine; the problem lies in part (C), where the phrase should be "greedy but also corrupt".

Verification / Alternative check:
Read the corrected sentence: "I am certain that the officer is not only greedy but also corrupt." This is a well balanced sentence in which "greedy" and "corrupt" are matched adjectives, joined by the complete correlative pair "not only … but also". Without "also", the sentence sounds incomplete and less formal, which is not acceptable in competitive exam standards.

Why Other Options Are Wrong:

• (A) I am certain that: Grammatically correct introduction to a dependent clause.
• (B) the officer is not only: Correctly sets up the first half of the correlative conjunction.
• (D) No error: Cannot be chosen because we have identified the missing "also" in part (C).

Common Pitfalls:
Students often overlook missing words in common idiomatic structures because the sentence still seems understandable. However, exams specifically test these standard patterns. Always check both halves of correlative pairs like "not only … but also", "either … or", "neither … nor", and "both … and". If one half is present, confirm that the corresponding partner is also there and that both sides are grammatically parallel.

Final Answer:
The error is in part C; the sentence should read "greedy but also corrupt."