Write $$L$$ for licensure, $$C$$ for certification, or $$R$$ for registration in the space provided to indicate which is applicable in the following descriptions.

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Involves a mandatory credentialing process established by law, usually at the state level.

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Initially started without any requirement or proof of competency.

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Involves a voluntary credentialing process, usually national in scope, most often sponsored by a private$-$sector group.

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Required of all physicians, dentists, and nurses in every state.

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Began as a simple entry in an official list.

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To obtain, one must complete a course of study, followed by an occupation$-$specific examination.