PLEASE HELP! Which issue is most closely associated with these headlines?
"Compromise Enables Maine and Missouri to Enter the Union"
"California Joins the Union as Part of Compromise of 1850"
"Kansas-Nebraska Act Establishes Popular Sovereignty in the Territories"

Select one:
a. influence of political parties on economic development
b. negotiation of the Oregon Treaty
c. expansion of land for reservations
d. status of slavery in new states