(A) of
(B) at
(C) by
(D) None of these
🧠 Explanation:
- Correct Answer: The correct option is by.
- Usage of "by": "By" is used when referring to the mode of transportation, such as by car, by bus, by plane, or by train.
- Explanation: The sentence indicates the mode of transportation used to travel to Karachi, which is "train" in this case.
- Incorrect Options: "Of" and "at" are not used in the context of modes of transport, which is why they are not appropriate here.
