Which of the following National Waterways is the longest in India?
1
West Coast Canal (Kottapuram - Kollam), Champakara and Udyogmandal Canals
2
Ganga-Bhagirathi-Hooghly River System (Haldia - Allahabad)
3
Brahmaputra River (Dhubri - Sadiya)
4
North Buckingham Canal (Peddaganjam to Central Station of Chennai)