The lifeline connecting major towns and cities in Meghalaya is:

National Highway 54
Eastern Dedicated Freight Corridor
Konkan Railway
Brahmaputra River System

The correct answer is: a) National Highway 54.

National Highway 54 is a national highway in India that runs from Guwahati in Assam to Shillong in Meghalaya. It is one of the most important highways in the region, connecting the two major cities and providing a vital link for trade and commerce. The highway is also a popular tourist destination, offering stunning views of the surrounding hills and valleys.

The other options are incorrect for the following reasons:

  • Option b, Eastern Dedicated Freight Corridor, is a freight railway line that is currently under construction. It will connect Ludhiana in Punjab to Dankuni in West Bengal, and will not pass through Meghalaya.
  • Option c, Konkan Railway, is a coastal railway line that runs from Mumbai in Maharashtra to Mangalore in Karnataka. It does not pass through Meghalaya.
  • Option d, Brahmaputra River System, is a river system that flows through the states of Assam, Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura, and Meghalaya. It is an important source of water for irrigation and drinking water, but it is not a major transportation route.