Final answer:
'All of the listed answers' as each location—Meuse Valley, Belgium; Donora, Pennsylvania; and London, England—experienced a major, lethal air pollution event in the early to mid-20th century.
Step-by-step explanation:
The location of a major lethal air pollution episode includes all of the listed answers: Meuse Valley, Belgium (1930); Donora, Pennsylvania (1948); and London, England (1952). These incidents highlight the severe impacts of industrial pollution and the lack of environmental regulation during those times.
In the Meuse Valley, Belgium, a deadly fog containing pollutants from industrial processes blanketed the region, leading to numerous deaths. The Donora smog in Pennsylvania was a result of emissions from steel and zinc plants. Similarly, the Great Smog of London was caused by cold weather combined with coal smoke, which led to a sharp increase in pollution-related health problems and deaths.