Final answer:
A New England abolitionist would have most likely opposed the Kansas-Nebraska Act because it opened new territories to the possibility of slavery and repealed a key anti-slavery provision of the Missouri Compromise. Therefore, the correct option is E.
Step-by-step explanation:
The individual most likely to have opposed the Kansas-Nebraska Act would be e. A New England abolitionist. The Kansas-Nebraska Act, proposed by Stephen Douglas, aimed to allow the possibility of slavery in the territories of Kansas and Nebraska. This was done through the principle of popular sovereignty, which let the inhabitants of these territories decide on the slavery issue.
The act also proposed the repeal of the 36° 30' line from the Missouri Compromise, which previously prohibited slavery north of this latitude. New England abolitionists, who were staunchly against the expansion of slavery, would have seen the Kansas-Nebraska Act as a dangerous step towards the spread of slavery into new territories.