Final answer:
The key Progressive item passed by Taft was the Pure Food and Drug Act. This act enacted federal standards of inspection and sanitation on meatpackers and required drug makers to list ingredients.
Step-by-step explanation:
The key Progressive item passed by Taft was the Pure Food and Drug Act. The Pure Food and Drug Act, passed in 1906, enacted federal standards of inspection and sanitation on meatpackers and required drug makers to list ingredients. This law was inspired by muckraking exposés about adulterated foods and dangerous patent medicines.