Which development would best serve as a turning point between two historical periods

The correct answer is Civil War.

A Civil War best serve as a turning point between two historical periods.

A turning point is the precise, specific or significant moment when something starts to change.

For instance, any Civil War has represented a turning point in the history of a nation. The Civil War in the United States changed the society of America, ending slavery in the country. The Civil War in Mexico, called the Mexican Revolution, transformed the political in the country. The Civil War ended the 33 years of power od Dictator Porfirio Diaz. This represented the entrance of Mexico in a more modern period of social equity.

affirmative action refers to the policies that take gender, race, or ethnicity into account in order to promote equal opportunity.

employers subject to title vii are prohibited from taking race or sex into account in any employment decisions. aa is a penalty for having any job group substantially statistically "underutilized" in any race or either sex. the employer must take steps to eliminate the underutilization, then stop, ending its aa efforts

worcester v. georgia, legal case in which the u.s. supreme court on march 3, 1832, held (5–1) that the states did not have the right to impose regulations on native american land. andrew jackson refused to enforce the ruling, the decision form the basis for most subsequent indian law in the united states.