Choose the sentence that has the incorrect preposition in it:

The correct answer is Option (1) → The train is running off time.

The phrase "off time" is incorrectly used. To indicate that a scheduled event is running late, the correct idiom is "behind time" or "late."

• Correction: The train is running behind time. (Meaning: late)

• Alternative Correction: The train is running on time. (Meaning: according to schedule).

  Other Options: The prepositions in the other sentences are used correctly:

  • It has been five years since I have seen my mother.

    • "Since" is correctly used here as a conjunction/preposition to indicate a point in time (the last time they saw each other) and the duration thereafter.

  • Sheela left for the station an hour ago.

    • "For" is correctly used to indicate the destination or goal of her departure.

  • Vineet studied till 1 am for his upcoming exam.

    • "Till" (or until) is correctly used to indicate the end point of a period of time.