Early in his presidency, abraham lincoln declared that his primary goal as president was to

a) preserve the union.

b) encourage sectionalism.

c) enforce the emancipation proclamation.

d) end slavery throughout the entire country.

A is  the correct answer

As for B he hated sectionalism he wanted to keep the united states, United
For C, the Emancipation Proclamation was not his primary goal only a stepping stone
For D, this was not his MAIN goal  he first had to worry about keeping the states united and the union preserved before he could think about ending slavery