The correct option is A Silencer
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Silencers control noise pollution while others control air pollution. To control the particulate matter in air, we need to deploy smoke stacks with electrostatic precipitators. Fabric filters, scrubbers, and inertial separators should be fitted to factories. Oil and gas can be used as alternatives to coal to reduce smoke in some of the industries. Noise pollution can be curbed by fitting silencers to generators.