1.CNG is a natural gas, nowadays use in vehicles. It is a good source of reducing pollution.
2. Alike CNG metro trains are the new modes of transport. Metro trains are fast they are reliable transportation.
3. Metro trains uses electricity to run and hence they do not use any fuel. Which results in no pollution. They need energy but Vehicle which runs on CNG gas needs this gas.
4 Thus, Metro trains are helpful in reducing pollution in Delhi.