The sentence is divided into four segments: (A), (B), (C), and (D). Identify the segment that contains a grammatical error. If the sentence is both grammatically and contextually correct, select “No error” as the correct answer.

Nobody saw (A)/ him since the balcony (B)/ collapsed during (C)/ the heavy storm. (D)

The correct option is A.

Detailed Explanation:

The given sentence is divided into four segments: "Nobody saw (A)", "him since the balcony (B)", "collapsed during (C)", and "the heavy storm. (D)".

The grammatical error lies in segment (A). The word since is used in segment (B) as a time conjunction to denote a starting point in the past (the moment the balcony collapsed) for an action or state that continues up to the present time.

In English grammar, when since is used in this manner, the main clause preceding it must use the present perfect tense rather than the simple past tense. This is because the action of not seeing him began in the past and continues to be true in the present.
Consequently, the simple past verb saw in segment (A) must be corrected to the present perfect form has seen (or "has seen" combined with "nobody" as the singular subject).

Therefore, the corrected sentence is:
"Nobody has seen him since the balcony collapsed during the heavy storm."