The twelfth amendment to the constitution, adopted in 1804:

The amendment was proposed by the Congress on December 9, 1803, and was ratified by the requisite three-fourths of state legislatures on June 15, 1804.

This question is incomplete, here's the complete question.

The Twelfth Amendment to the Constitution, adopted in 1804:

A. required the electoral college to vote separately for president and vice president

B. created a new federal judiciary system with John Marshall as Chief Justice of the United States

C. institutionalized the two-party system in American politics

D. established the sovereignty of the national government over the state governments

Answer: A. required the electoral college to vote separately for president and vice president

Explanation:

The presidential election of 1800 exhibited the increasing power of political parties and severe problems of the election process. Still following the original stipulations of the Constitution, there was still a voting privilege, with elite slates of electors choosing the president and vice president. The 12th Amendment, first applied in the election of 1804, established separate votes for presidential and vice-presidential candidates, reviewing flaws in the previous electoral system.