Q. Which of the following city is known by the name of the city of smoke?

Explanation by: Mr. Dubey

Lanzhou, China, is known as the "City of Smoke" due to its severe air pollution and industrial smog. The city's geography, surrounded by mountains, traps pollution, leading to poor air quality.

Other options:

London (B) → Known as the "City of Fog" due to historical smog issues.

Kolkata (C) → Not commonly associated with the "City of Smoke."

Chicago (D) → Known as the "Windy City," not the "City of Smoke."