The correct answer is: A. Ambala
Ambala is a city in the Indian state of Haryana. It is located
in the Ambala district, which is in the north-western part of the state. Ambala is the oldest railway station in Haryana, and it was established in 1873. It is also the biggest railway station in the state.Rewari is a city in the Indian state of Haryana. It is located in the Rewari district, which is in the south-western part of the state. Rewari is not the oldest railway station in Haryana, and it was not established in 1873.
Sirsa is a city in the Indian state of Haryana. It is located in the Sirsa district, which is in the south-western part of the state. Sirsa is not the oldest railway station in Haryana, and it was not established in 1873.
Hansi is a city in the Indian state of Haryana. It is located in the Hisar district, which is in the north-western part of the state. Hansi is not the oldest railway station in Haryana, and it was not established in 1873.