The invention of which of the following revolutionised road transport?

Internal combustion engine

The correct answer is option 2: Internal combustion engine

The invention of the internal combustion engine revolutionised road transport by enabling the development of automobiles such as cars, buses, and trucks, making transport faster and more efficient.

Option 1: Engine — Incorrect. This is a broad term and does not specifically refer to the invention that transformed road transport.

Option 3: Steam Engine — Incorrect. The steam engine mainly revolutionised rail and water transport rather than road transport.

Option 4: Diesel Engine — Incorrect. The diesel engine was developed later as a type of internal combustion engine and improved transport efficiency, but the major revolution in road transport began with the invention of the internal combustion engine.

NCERT: ..." The revolution in transport came about only after the invention of the steam engine in the eighteenth century. Perhaps the first public railway line was opened in 1825 between Stockton and Darlington in northern England and then onwards, railways became the most popular and fastest form of transport in the nineteenth century. It opened up continental interiors for commercial grain farming, mining and manufacturing in U.S.A. The invention of the internal combustion engine revolutionised road transport in terms of road quality and vehicles (motor cars and trucks) plying over them. Among the newer developments in land transportation are pipelines, ropeways and cableways. Liquids like mineral oil, water, sludge and sewers are transported by pipelines. The great freight carriers are the railways, ocean vessels, barges, boats and motor trucks and pipelines."