The zone with the minimum length is

North - Eastern Railway
North - Eastern Frontier Railway
South - East Railway
South - Central Railway

The correct answer is: South – Central Railway.

The South Central Railway (SCR) is one of the 17 zones of Indian Railways. It is headquartered in Secunderabad, Telangana. The SCR has a total route length of 6,252 km, making it the shortest zone in India.

The North Eastern Railway (NER) has a total route length of 10,304 km. The North Eastern Frontier Railway (NFR) has a total route length of 8,542 km. The South East Railway (SER) has a total route length of 10,027 km.

The SCR is divided into 10 divisions:

  • Secunderabad Division
  • Hyderabad Division
  • Vijayawada Division
  • Guntur Division
  • Kurnool Division
  • Nanded Division
  • Latur Division
  • Bhusaval Division
  • Nagpur Division
  • Bhopal Division

The SCR operates a variety of passenger and freight trains. It also operates a number of special trains, such as the Rajdhani Express, the Shatabdi Express, and the Duronto Express.

The SCR is a major employer in the region. It provides employment to over 200,000 people. The SCR is also a major contributor to the economy of the region. It generates over ₹100 billion in revenue each year.