The following sentence has been divided into three segments. One of them may contain an adverbial usage error. Select the option that has the segment with the error. If you don’t find any error, select ‘No error’ as your answer.
Mr. Narayanan / is a rather / lazy man.

The correct answer is No error.

Let us analyze the given sentence by examining each segment:

1. Mr. Narayanan: This is the subject of the sentence, which is a singular proper noun properly introduced.

2. is a rather: The verb "is" links the subject to the noun phrase. The word "rather" is used here as a degree adverb modifying the adjective "lazy". Placing "rather" before the indefinite article "a" (e.g., "rather a lazy man") or after it (e.g., "a rather lazy man") are both grammatically correct in standard English. Here, "a rather lazy man" is perfectly valid.

3. lazy man: "lazy" is an adjective correctly modifying the singular countable noun "man".

Since all parts of the sentence adhere to standard English rules of grammar and adverb usage, there is no error in the sentence.