Which group, the abolitionists, the government, or the enslaved themselves were most effective in ensuring the enslaved were freed?

Abolitionists

Explanation:

They hate slavery and thought it was cruel. Before slavery ended, they wanted all black people to be free

necessary and proper clause. the congress shall have power to all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states, or in any department or officer thereof.

presidency should be the title