Option 1 suggests that Indian railways system is the largest in the world and National Highways cater to 45 per cent of the total road transport demand. The second part is correct but the first part isn`t true as Indian rail system is one of the largest but not the largest; Russia has the largest by size.
Option 2 states that Indian railways system is the largest in the world and Kerala has the highest density of surface road. Both statements are incorrect as Russia has the largest railways, and in terms of road density, it is not Kerala but Delhi that has the highest density as per the latest data.
Option 3 suggests the National Highways cater to 45 per cent of the total road transport demand and Kerala has the highest density of surface road. Although highways do carry a significant amount of transport demand, it does not account for 45%. Also, Kerala doesn`t have the highest road density- it is Delhi.
Option 4, which is the correct answer, proposes that National Highways cater to a significant chunk of the total road transport demand and that National Highway No. 7 is the longest in the country. National Highway No. 44 (formerly known as No. 7) is indeed the longest in India, spanning from north to south.