The was important because it stopped meat packers from including meat from diseased animals in processed meat for sale.

The Meat Inspection Act established federal inspections of meat-processing plants and prohibited the sale of meat from diseased animals. This directly addressed unsafe meat, so the correct choice is the Meat Inspection Act. The Pure Food and Drug Act focused more broadly on adulterated or misbranded foods and medicines, while the Northern Securities case concerned a railroad trust.

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