The following sentence has been split into four segments. Identify the segment that contains a grammatical error.
A. He usual jogs in the early morning, /
B. enjoying the fresh air and peaceful atmosphere /
C. while preparing for /
D. the upcoming marathon.

Correct option is C

Option (c) contains an error.
Explanation: "usual" is an adjective, but here we need an adverb to modify the verb "jogs". The correct word is “usually”.
Correct sentence: He usually jogs in the early morning, enjoying the fresh air and peaceful atmosphere while preparing for the upcoming marathon.
Grammatical rule used:
✅ Adverbs of frequency like “usually”, “often” modify verbs and are placed before the main verb.
Example: She usually reaches school by 8 AM.
�� Information Booster: Avoid using adjectives where adverbs are required to describe actions.