In almost all Indian metropolitan cities like Delhi,the major atmospheric pollutant$(s)$ is/are

Carbon monoxide is a major pollutant of

Consider the following statements about a scrubber:
$I.$ It is used to remove gases like sulphur dioxide from industrial exhaust.
$II.$ In a scrubber,the exhaust is passed through a spray of water or lime.
$III.$ Water dissolves gases and lime reacts with sulphur dioxide to form a precipitate of calcium sulphate or calcium sulphide.
Which of the statements given above are correct?

Which of the following is the largest source of air pollution these days?

Which of the following measures have been taken by the Government of India to control air pollution?

The Air (Prevention and Control of Pollution) Act came into force in ........