One of the main groups in the early 1800s to object morally to slavery was the: Southern plantation owners
O Quakers
New England merchants

The answer is indeed Quaker.

Explanation: One of the main groups in the early 1800s to object morally to slavery was the: Quakers

workers of lowell mills were greatly benefited for the waltham type of work which was more a paternalist kind, trying to protect the integrity of this little girls coming from small farmers and providing an adequate place of work, this in an effort to avoid the issues of bad place conditions and immorality that the people in bigger industrialized cities of great britain were experimenting.