Since 1980, the distance between the congressional parties has been growing steadily. this trend is called

This trend is called Polarized politics or politic polarization.
We can define polarization in politics as it can allude to the disparity of political states of mind to ideological extremes and it can allude to such dissimilarity like popular conclusion or even to such uniqueness inside certain groups.Almost all exchanges of polarization in political science consider polarization with regards to political gatherings and vote based frameworks of government. At the point when polarization happens in a two-party framework, similar to the United States, direct voices frequently lose power and impact.

Your answer is a distributive