Which piece of legislation played the greatest role in michigan's admission to the union as a free state in 1837? a) the adams-onis treaty b) the compromise of 1820 c) the northwest ordinance d) the virginia resolution

The piece of legislation that played the greatest role in Michigan's Admission was the The compromise of 1820  

Explanation:

The Northwest ordinance chartered a government for the northwest territories of which Michigan was part of the northwest it provided a method of admitting new states into the union from the region but the compromise of 1820 played the greatest role in admitting it as a free state because the compromise made all western territories north of Missouri' southern border to be admitted as free state on March 3 1820