Identify the devices and legal mechanisms that were employed to prevent african americans from voting.

the devices used to prevent African Americans from voting was voter qualifying tests (e.g., literacy tests), discriminatory enforcement of registration rules, poll taxes, there was also the grandfather clause that stated if you have a ancestor that voted before you it entitles you to voting without taking any test. 

north atlantic treaty organization.

the answer is c, all the other options are things they are known for.

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