The correct answer is: d) All of the above
Sikkim is a mountainous state in northeastern India. It is bordered by Bhutan to the north, China to the east, Nepal to the west, and West Bengal to the south. The state has a population of about 610,000 people and a land area of about 7,096 square kilometers.
The mountainous terrain of Sikkim makes it difficult to build and maintain a well-developed network of transportation infrastructure. Waterways, high-speed trains, and subways are all types of transportation that are difficult to build and maintain in mountainous terrain.
Waterways are difficult to build and maintain in mountainous terrain because the rivers are often turbulent and the terrain is often steep. High-speed trains are also difficult to build and maintain in mountainous terrain because the terrain is often uneven and the tunnels that are needed to build high-speed trains are expensive to construct. Subways are also difficult to build and maintain in mountainous terrain because the terrain is often uneven and the tunnels that are needed to build subways are expensive to construct.
Due to the mountainous terrain, Sikkim does not have a well-developed network of any of these types of transportation. The state’s transportation infrastructure is limited to roads and air travel.