WAEC - Biology (1990 - No. 42)

Which of the following is not a way of reducing air pollution?

Siting factories and power stations away from residential areas

Building tall factory chimneys

Passing waste gases through filters and absorbers

Using lead-free petrol in cars

Recycling tins, cans and bottles

All the options contribute to the reduction of air pollution except option E which does not in any way reduce air pollution.