D) Slavery was allowed in some parts of the territory but not allowed in other parts.
Explanation:
When the Missouri Treaty was first applied in 1818, many of areas still wanted to allow slavery in Louisiana Purchase Territory. Due to the increased tensions over the issue of slavery, especially to deal with the spread of slavery in western territory, the Missouri Compromise in 1820 divided the state of Louisiana Purchase into 2 parts. Slavery was allowed south of latitude 36 degrees 30' and the in the north of that, slavery was forbidden. Few exception included Missouri which became a slave state, and Maine which became a free state
