Poll taxes, literacy tests and threatened violence were all measures that existed in Southern states in order to undermine the content of A) the 15th Amendment. This was due to the South having a hard time coming to terms with the fact that they were obligated to give African-Americans equal voting rights. The above were both harsha and offensive tactics used against former slaves, so that they were unable to vote.
A b c or d is that in this question
<span>Sexual reproduction INCREASES variation and selective breeding DECREASES variation.
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