The correct answer is C) embargo.
The type of trade barrier would guarantee that no child in the United Kingdom would be exposed to the deadly lead-based paint is called an embargo.
When a situation like this presents itself, the government has to take special measures to protect the citizens of its country. An embargo is a restriction of commerce ordered by the federal government through its Department of Commerce. This embargo prohibits country "A" from buying and importing products from country "B." In situations like this is when countries ask the intervention of the World Trade Organization (WTO) in order to negotiate and get a resolution that favors both countries.