which of the following categories within the skin corrosion/irritation hazard class would be assigned to the most hazardous skin corrosives?

Category 1A is assigned to the most hazardous skin corrosives within the Skin Corrosion/Irritation hazard class.

In other words, if you see options like 1A, 1B, 1C, and 2, the correct choice for “most hazardous skin corrosives” is 1A.

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