Final answer:
The phrase 'legitimate discontent' in the quote represents an example of charged language, conveying a powerful sense of justification and unrest.
Step-by-step explanation:
The phrase that best represents an example of charged language in the quote, "The sweltering summer of the Negro’s legitimate discontent will not pass until there is an invigorating autumn of freedom and equality," is legitimate discontent. This phrase is charged because it conveys a powerful sense of justification and unrest within the African-American community during their struggle for civil rights. The words freedom and equality also carry emotional weight, resonating with the desires and struggles of the community.