Democratice-Republicans that supported Jefferson came mostly from which part of the
country?

The Southern part.

Explanation:

Thomas Jefferson was a famous anti-federalists. He believed that the central government should give a lot of freedom for individual states to create legislations by their own without many interference from the central government.

This view was really popular among the people Southern states since many of them believed that interference from Federal government massively hurt their economy. (For example, the southern states often protested Federal Government's policy to increase taxes for imported product that mostly bought in southern states)

the answer might be either a or c. can't be too sure , because i searched the web, but no valid answers came through.

can you explain it better