HELP ASAP PLEASE!!! ILL GIVE BRAINLEST!!

why was James Monroe's presidency known as the "Era Of Good Feelings?"

A. ) The united states didn't have any problems with foreign nations.
B. ) a feeling of nationalism and there was only 1 political party the democratic republicans
C. ) The entire nation was happy with the building of the Erie canal
D. ) The federalists and democratic-Republican agreed to work together and not argue.