The most important achievement of the India railways is the construction of Konkan railway line. This railway line covers the states of

Maharashtra, Goa, Karnataka

The correct answer is Option (3) → Maharashtra, Goa, Karnataka

• One of the important achievements of the Indian Railways has been the construction of Konkan Railway in 1998.
• It is 760-km long rail route connecting Roha in Maharashtra to Mangalore in Karnataka.
• It is considered an engineering marvel.
• It crosses 146 rivers, streams, nearly 2000 bridges and 91 tunnels.
• Asia's largest tunnel which is nearly 6.5 km long, also lies on this route.
• The states of Maharashtra, Goa and Karnataka are partners in this undertaking.