Which of the following best describes what led to london’s “killer fog” in 1952? a. pollution from the air contaminated the water supply which is what killed people. b. millions of coal fires and stagnant air caused toxic fumes to build up in the air. c. poor city design led to faulty ventilation in houses. d. soot from forest and wildfires in the surrounding areas blew over the city.

The correct answer is - b. Millions of coal fires and stagnant air caused toxic fumes to build up in the air.

The ''killer fog'' in London in the year of 1952, was such a dense smog that the breathing of the people was extremely hard, they were getting respiratory problems, and even the view was limited to just few meters. The cause for the appearance of this extreme case of smog was mainly the coal, since it was still used for heating up the homes, as well as being heavily used by the industry, there were millions of coal fires in London and its surrounding area, so the emissions of carbon dioxide and carbon monoxide were extremely big. ON top of that, the air was very stagnant, so the was no natural cleaning of the air, but instead it was just building up in one place.