Question

Long chimneys in factories are to ________.

• A. make it beautiful
• B. increase the efficency of factory
• C. release harmful smoke high in the atmosphere
• D. reduce the cost of production

Answer 1

The correct option is C

release harmful smoke high in the atmosphere

The burning of fuel produces smoke. Smoke contains a few gases and fine dust particles and is often harmful. That is why we have long chimneys in factories. This takes the harmful smoke and gases away from the breathing level of the living organism and releases it high in the atmosphere.