Which of the tracks is called the India gauge?

1. Narrow Gauge
2. Metre Gauge
3. Broad Gauge
4. All of the above.

Assertion (A): Railway system has been divided into 18 zones.

Reason (R): Indian Railways' huge size will put pressure on a centralised management system.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.

Which of the following is an advantage of airways?

1. Ease of crossing difficult terrain
2. Dependency on weather conditions
3. Carriage of low tonnage
4. Fuel used is petroleum

Of the total navigable length of 20,236 km, 17,980 km of the river and 2,256 km of canals can be used by mechanised flat bottom vessels. Which transport is referred to here?

1. Inland waterways
2. Oceanic waterways
3. Motorways
4. All of them.